When running the program for the first time, no scene collections will
show up in the scene collection menu.  This changes it to forcibly save
the first scene collection on the first run of the program, and then
re-enumerates the list to ensure it's listed.

obs_service_update was left out by accident in the previous commit.

Removes advanced encoder settings from final wizard result so they don't
conflict with the wizard's expected final results.

Fixes some cases where the maximum bitrate might not be capped by the
service selection as it's supposed to be.

Fixes potential decoding errors with FFmpeg's new decode API.  Because
avcodec_send_packet may process multiple packets, you must call
avcodec_receive_frame continually until no more frames are left.

Prevents potential decoding issues by relying on FFmpeg to manage
sub-packet handling.

Allows adding minor video delay to non-async sources.

Allows directly rendering a non-async source without going through
filters.

Prevents the media playback object from locking the render thread.

Will cause avformat to lock up perpetually on av_read_frame.

Fixes a bug where loading vertex shaders could cause error messages
about mismatching vertex buffer data to appear because the vertex shader
would try to reload the previously used vertex buffer.

This commit fixes creating log files in windows with Unicode profile
names.

I encountered this bug when running obs-studio 18.0.2 in Windows 8.1 x64
with my user profile path containing Unicode characters.

Steps to reproduce:

1) Create a windows user with a Unicode name: "пользователь"
2) Run OBS Studio, go to Help -> Log Files -> View current log (Nothing
happens)

The expected result is opening current log file.

Closes jp9000/obs-studio#916

CI: exclude .gitignore from AppVeyor artifacts

Failure to decode is unfortunately quite common with certain file types,
and is most of the time safely recoverable.  There's no reason to
actually output a log message for this unless really needed.

There's a loophole that would allow users to activate an output while in
the settings window via hotkeys -- this prevents that from being able to
happen.  Note that users can still shut down outputs, but they can no
longer start them up while in the settings window.

While an output is active, the user may try to reset the settings in the
settings window, causing a misleading error message to be thrown in the
log indicating that it's "falling back" to OpenGL.

Instead, if an output is currently active, do not reset video.

Adds a method of uniquely identifying scene items, as well as finding
those scene items via that unique ID.

Fixes a bug where the individual drop-down lists of each quick
transition would not have the correct available transitions listed if
transitions were added, renamed, or removed

enc-amf: Version 2.1.3

Adds an option that allows the user to specify the size (or aspect) of
the bounding source size which all the images are then scaled in to.
Acts similarly to "bounding box" of scene items, but for the slide show
and its sub-sources.

Uses a named mutex to detect if multiple instances of the program are
open, and if so warns the user.  When running in portable mode, uses a
separate unique mutex name mapped to the user's config directory to
ensure that no two portable builds use the same config directory.  This
way, portable builds do not conflict with normal builds or other
separate portable builds.

"OldDefaults" was changed to "Pre19Defaults", but it was still left in
this spot unchanged.

Instead, quit only when the main window has been fully closed (and not
minimized to tray).  Fixes a bug where if the main window is minimized
to tray and another non-child window is open (for example, the stats
window), and then that window is closed, would cause the program to
prematurely exit and crash.

(This commit also modifies the decklink, linux-v4l2, mac-avcapture,
obs-ffmpeg, and win-dshow modules)

Originally, async buffering for sources was supposed to be a
user-controllable flag.  However, that turned out to be less than ideal
because sources (such as the win-dshow plugin) were programmed with
automatic control over their buffering (such as automatically detecting
USB 2.0 capture devices and then enabling in those cases).

The fact that it was a flag caused a design flaw to where buffering
values would be overwritten when a source is loaded from save data.

Because of that, this flag is being deprecated and replaced with a
specific function to enable unbuffered mode instead.