For the sake of consistency, changed allow_direct_render to
obs_allow_direct_render

Prefix with obs_ for the sake of consistency

Renamed enums:
- order_movement (now obs_order_movement)

Affected functions:
- obs_source_filter_setorder
- obs_sceneitem_setorder

For the sake of naming consistency with the rest of obs.h, prefix this
structure and associated functions with obs_.

Renamed structures:
- struct source_frame (now obs_source_frame)

Renamed functions:
- source_frame_init (now obs_source_frame_init)
- source_frame_free (now obs_source_frame_free)
- source_frame_create (now obs_source_frame_create)
- source_frame_destroy (now obs_source_frame_destroy)

Affected functions:
- obs_source_output_video
- obs_source_get_frame
- obs_source_release_frame

Renamed functions:
- obs_source_getframe (rename to obs_source_get_frame)
- obs_source_releaseframe (rename to obs_source_release_frame)

For the sake of consistency and helping to get rid of the "squishy
function name" issue

With the recent change to module handling by BtbN, I felt that having
this information might be useful in case someone is actually using make
install to set up their libraries.

NOTE: In texture_setimage, I had to move variables to the top of the
scope because microsoft's C compiler will give the legacy C90 error of:
'illegal use of this type as an expression'.

To sum it up, microsoft's C compiler is still utter garbage.

Similar to the shader functions, the effect parameter functions take
the effect as a parameter.  However, the effect parameter is pretty
pointless, because the effect parameter.. parameter stores the effect
pointer interally.

The locale parameter was a mistake, because it puts extra needless
burden upon the module developer to have to handle this variable for
each and every single callback function.  The parameter is being removed
in favor of a single centralized module callback function that
specifically updates locale information for a module only when needed.

This replaces the older code which simply queried the max volume level
value for any given audio.

I'm still not 100% sure on if this is how I want to approach the
problem, particularly, whether this should be done in obs_source or in
audio_line, but it can always be moved later if needed.

This uses the calculations by the awesome Bill Hamilton that OBS1 used
for its volume levels.  It calculates the current max (level),
magnitude, and current peak.  This data then can be used to create
awesome volume meter controls later on.

NOTE: Will probably need optimization, does one float at a time right
now.

Also, change some of the naming conventions.  I actually need to change
a lot of the naming conventions in general so that all words are
separated by underscores.  Kind of a bad practice there on my part.

This allows sources to optionally defer update on creation in order to
prevent updates from being called from threads other than the video
thread.

When a source's private data is being created by a module, it wasn't
able to call most source functions because most functions rely on the
obs_source_info part of the context to be set.  This fixes that issue.

It was strange that this wasn't already the case because the other
context types already did the same thing.

This uses the reverse planar YUV 4:2:0 conversion shader to output a YUV
texture without having to convert it via CPU.  Again, this will reduce
video upload bandwidth usage to 37.5% of the original rate.  I suspect
this will be particularly useful for when an FFmpeg or libav input
plugin for playing videos is made.

NOTE: There's an issue with certain texture sizes right now I haven't
been able to identify, if the full size of texture data divided by the
base texture width is an uneven number, the V chroma plane seems like it
can potentially shift, though I only had this happen with 160x90
resolution C920.  Almost all resolutions tend to be even.  Needs further
testing with more devices that support planar YUV 4:2:0 output.

First, if the private data of the source fails to be created, then do
not destroy the source.  If the source is destroyed, all the user's data
associated with that source is lost, which could end up being a
potential problem.  Instead, let it linger as a 'dead' source until the
user chooses to fix the problem (though this should never really happen,
the source module functions should be programmed to handle this
scenario)

Secondly, rename new_frame_ready to ready_async_frame, and fix a
potential memory leak with it.

obs_source_output_video can cause cached frames to be freed twice if
called with a partially destroyed source, among other undesirable
effects; freeing the source private data right after the destroy signal
has been processed ensures proper behavior

 - Add volume control

   These volume controls are basically nothing more than sliders.  They
   look terrible and hopefully will be as temporary as they are
   terrible.

 - Allow saving of specific non-user sources via obs_load_source and
   obs_save_source functions.

 - Save data of desktop/mic audio sources (sync data, volume data, etc),
   and load the data on startup.

 - Make it so that a scene is created by default if first time using the
   application.  On certain operating systems where supported, a default
   capture will be created.  Desktop capture on mac, particularly.  Not
   sure what to do about windows because monitor capture on windows 7 is
   completely terrible and is bad to start users off with.

If a source with async video wasn't currently active, it would endlessly
buffer the video data, which would cause memory to grow endlessly until
available memory was extinguished.

This really needs to be replaced with a proper caching mechanism at some
point.

This saves scenes/sources from json on exit, and properly loads it back
up when starting up the program again, as well as the currently active
scene.

I had to add a 'load' and 'save' callback to the source interface
structure because I realizes that certain sources (such as scenes)
operate different with their saved data; scenes for example would have
to keep track of their settings information constantly, and that was
somewhat unacceptable to make it functional.

The optional 'load' callback will be called only after having loaded
setttings specifically from file/imported data, and the 'save' function
will be called only specifically when data actually needs to be saved.

I also had to adjust the obs_scene code so that it's a regular input
source type now, and I also modified it so that it doesn't have some
strange custom creation code anymore.  The obs_scene_create function is
now simply just a wrapper for obs_source_create.  You could even create
a scene with obs_source_create manually as well.

Add API for streaming services.  The services API simplifies the
creation of custom service features and user interface.

Custom streaming services later on will be able to do things such as:

 - Be able to use service-specific APIs via modules, allowing a more
   direct means of communicating with the service and requesting or
   setting service-specific information

 - Get URL/stream key via other means of authentication such as OAuth,
   or be able to build custom URLs for services that require that sort
   of thing.

 - Query information (such as viewer count, chat, follower
   notifications, and other information)

 - Set channel information (such as current game, current channel title,
   activating commercials)

Also, I reduce some repeated code that was used for all libobs objects.
This includes the name of the object, the private data, settings, as
well as the signal and procedure handlers.

I also switched to using linked lists for the global object lists,
rather than using an array of pointers (you could say it was..
pointless.)  ..Anyway, the linked list info is also stored in the shared
context data structure.

Before, async video sources would flicker because they were only being
drawn when they were updated.  So when updated, they'd draw that frame,
then it would stop drawing it until it updated again.  This fixes that
issue and they should now draw properly.

Also, fix a few other minor bugs and issues relating to async video,
and make it so that non-async video filters can be properly applied to
them.

For the purposes of testing, change the 'test-random' source to an async
video source that updates every quarter of a second with a new random
face.

Also fix a bug where non-async video sources wouldn't have filter
effects applied properly.

 - Implement the RTMP output module.  This time around, we just use a
   simple FLV muxer, then just write to the stream with RTMP_Write.
   Easy and effective.

 - Fix the FLV muxer, the muxer now outputs proper FLV packets.

 - Output API:
   * When using encoders, automatically interleave encoded packets
     before sending it to the output.

   * Pair encoders and have them automatically wait for the other to
     start to ensure sync.

   * Change 'obs_output_signal_start_fail' to 'obs_output_signal_stop'
     because it was a bit confusing, and doing this makes a lot more
     sense for outputs that need to stop suddenly (disconnections/etc).

 - Encoder API:
   * Remove some unnecessary encoder functions from the actual API and
     make them internal.  Most of the encoder functions are handled
     automatically by outputs anyway, so there's no real need to expose
     them and end up inadvertently confusing plugin writers.

   * Have audio encoders wait for the video encoder to get a frame, then
     start at the exact data point that the first video frame starts to
     ensure the most accrate sync of video/audio possible.

   * Add a required 'frame_size' callback for audio encoders that
     returns the expected number of frames desired to encode with.  This
     way, the libobs encoder API can handle the circular buffering
     internally automatically for the encoder modules, so encoder
     writers don't have to do it themselves.

 - Fix a few bugs in the serializer interface.  It was passing the wrong
   variable for the data in a few cases.

 - If a source has video, make obs_source_update defer the actual update
   callback until the tick function is called to prevent threading
   issues.

Improve the properties API so that it can actually respond somewhat to
user input.  Maybe later this might be further improved or replaced with
something script-based.

When creating a property, you can now add a callback to that property
that notifies when the property has been changed in the user interface.
Return true if you want the properties to be refreshed, or false if not.
Though now that I think about it I doubt there would ever be a case
where you would have this callback and *not* refresh the properties.

Regardless, this allows functions to change the values of properties or
settings, or enable/disable/hide other property controls from view
dynamically.

 - Add a properties window for sources so that you can now actually edit
   the settings for sources.  Also, display the source by itself in the
   window (Note: not working on mac, and possibly not working on linux).

   When changing the settings for a source, it will call
   obs_source_update on that source when you have modified any values
   automatically.

 - Add a properties 'widget', eventually I want to turn this in to a
   regular nice properties view like you'd see in the designer, but
   right now it just uses a form layout in a QScrollArea with regular
   controls to display the properties.  It's clunky but works for the
   time being.

 - Make it so that swap chains and the main graphics subsystem will
   automatically use at least one backbuffer if none was specified

 - Fix bug where displays weren't added to the main display array

 - Make it so that you can get the properties of a source via the actual
   pointer of a source/encoder/output in addition to being able to look
   up properties via identifier.

 - When registering source types, check for required functions (wasn't
   doing it before).  getheight/getwidth should not be optional if it's
   a video source as well.

 - Add an RAII OBSObj wrapper to obs.hpp for non-reference-counted
   libobs pointers

 - Add an RAII OBSSignal wrapper to obs.hpp for libobs signals to
   automatically disconnect them on destruction

 - Move the "scale and center" calculation in window-basic-main.cpp to
   its own function and in its own source file

 - Add an 'update' callback to WASAPI audio sources

Also, rename atomic functions to be consistent with the rest of the
platform/threading functions, and move atomic functions to threading*
files rather than platform* files

Automatically query defaults for sources/outputs/encoders and set them
before calling create

Ensure that a source has a valid name.  Duplicates aren't a big deal
internally, but sources without a name are probably something that
should be avoided.  Made is so that if a source is programmatically
created without a name, it's assigned an index based name.

In the main basic-mode window, made it check to make sure the name was
valid as well.