Follow-up to 47aa56b3 (PR #620). Windows 10 revision detection broke in
Build 15036 (Creators Update) after Revision 296. This aims to further
fix revision detection on Windows 10.

Allows setting a specific graphics adapter index to use for Direct3D 11.
This is currently meant to be sort of "undocumented" in implementing it
this way due to the fact that users will be guaranteed to break their
configurations if this is implemented in the UI (even if in advanced
settings).

Sets the swap interval to 0 to prevent v-sync from affecting any of the
preview panes on mac.

The cmake script code used to find and depend on pulseaudio for audio
monitoring on linux was unintentionally being triggered on mac.  This
patch makes it so that the pulseaudio cmake code is ignored on mac.

These code paths had no logging on failure, resulting in a log file that
would confuse people attempting to perform support for users.

Video playback doesn't work if the default format is MJPEG and there are
other formats to use; this is because the useDefaultConfig variable is
still set to true, which overrides the format value that would normally
tell it to convert to RGB.

This changes it so that the chooses indices at random from an index list
until the index list is exhausted.

Ensures that any rand() calls in the video thread will have a unique
seed to start from.

"Life is Feudal: Your Own" will use Direct3D to render the game, then
OpenGL to render its in-game menus, which causes a conflict with itself.
This specifically blacklists the game from capturing OpenGL to prevent
that from happening.

Makes it so that the settings do not update every time the user touches
a property of the source, but instead update when the user is finished.

This function had a number of bugs and just wasn't working properly at
all.  This function is currently not used in public builds because GPU
is used for color conversion instead (hence why it had probably not
really been tested), but a need came up where CPU conversion was useful
for the sake of testing something else in the back-end, and it needed to
be fixed before CPU conversion could be used.

The async source sync test verifies that async sources are playing back
in sync properly, and the "sync pair (video)" and "sync pair (audio)"
sources test the back-end syncing down to the exact sample via inserting
audio data directly in to the back-end with system timestamps.

For these sources, when the video is white, a C sinewave should be
playing, and when the video is black audio is mute.

It would appear that the timestamp values returned by devices are not
perfectly accurate, and in some cases may be calculated on the spot --
to combat that, it's best to subtract the audio segment's duration from
the current audio segment's timestamp to ensure the timing is as
accurate as possible.

Removes the unnecessary buffering from window capture to prevent window
capture from being one frame out of sync

When an async video frame comes in and it sets the timing_adjust value
(used to sync audio to video based upon their timestamps), it would use
os_gettime_ns as a base.  Instead, it should use OBS' current video
frame time so that the audio and video playback is as accurate as
possible relative to the actual exact timestamp of the video frame.
(Results are almost insignificant, but it's nice to be as precise as
possible)

Fixes up the FLV output to ensure it functions properly.

During packet interleaving (for outputs), ensure that if two packets
coincide with the same timestamp, that the video packet always comes
first instead of the audio packet.

This fix is required to make FLV demux properly with certain demuxers;
some FLV demuxers expect the video packet before the audio packet when
two packets coincide with the same timestamps.

The end of an FLV tag would contain the size of the tag, but the code
was erroneously including the end size value in addition, which it's not
supposed to do normally.

Modifying this value would cause the entire project to recompile when
it's only used in one file in the first place.

(This commit also modifies the obs-outputs module)

The first video packet video offset (the value used to set the starting
point of video data) would be set to the DTS value of the first video
packet.  However, when b-frames are used, the first DTS value will be
negative.  This was originally done because FLV muxing requires that the
first packet's DTS start from 0.  Unfortunately, this would also
effectively cause the first packet's PTS/DTS value to be shifted forward
by the negative amount, which would cause video sync to be off by a
video frame or two.

This fixes it to start at the PTS value instead and preserve any
negative offsets.  Additionally, the FLV muxing code has been fixed to
ensure that it adjusts the starting video DTS to 0, and now correctly
adjusts the first audio packet's timestamp according to that DTS as well
(which it didn't do before).

On audio encoder startup, audio encoders paired with a video encoder
would unintentionally discard a single audio data segment, causing it to
be 1024 audio frames out of sync.

On Windows 7, WinHTTP defaults to using only SSL3 and TLS 1.0. The
obsproject.com server was updated to remove TLS 1.0 support and
this has caused updates to stop working on Windows 7.

Certain PSAPI functions moved to KERNEL32 after Vista, setting
PSAPI_VERSION 1 uses the old PSAPI exports for compatibility. Vista
support was unintentionally broken by a6318ffd.

(This commit also modifies deps/media-playback)

Before, the media-playback library would detect whether something was
seekable by checking the filename for "://", which is unideal because
there are other cases where targets may not be seekable.  So instead, an
explicit "seekable" property (off by default) is now in place in the
media source when not in "local file" mode.  Seeking will only be
enabled if local file mode is on, or if "seekable" is explicitly checked
by the user.

Closes jp9000/obs-studio#1022

Prevents a potential cross-lock deadlock.  The UI thread would lock the
scene's mutex in obs_scene_atomic_update, then the item would lock the
graphics context to create a texture.  Meanwhile in the video thread, it
could lock the graphics context in the render loop, then lock the
scene's mutex when rendering.  When doing anything graphics-related, the
graphics context is always supposed to be locked before the scene's
mutex is supposed to be locked (it's designed that way), and the
obs_scene_atomic_update would just bypass that.

Add option in properties that let you choose how audio is mixed during
transition:
- Fade Out/Fade In (existing behavior, default)
- Crossfade

Closes jp9000/obs-studio#1028

Closes jp9000/obs-studio#1001

Replay buffer is currently only supported in simple mode.  This change
adds support to advanced mode and is, for the most part, a mirror of the
addition of replay buffer to simple mode.

Mantis-bug: https://obsproject.com/mantis/view.php?id=792

Closes jp9000/obs-studio#1019

libobs: Fix a potential divide by zero crash

UI: Fix parent window geometry loading

UI: Allow volume peak to be customized via .qss

Change 'but both were not found' to 'but neither were found.'

Closes jp9000/obs-studio#1018

With certain combinations of CMake (<3.9) and ImageMagick (>=7),
configure will silently fail setting up support for ImageMagick,
even if the user requested for it, and the build will move on
(as long as FFMPEG_AVCODEC is found).  This commit adds a check
that will stop configure in such cases.

Closes jp9000/obs-studio#1018

Since ImageMagick 7, the header path has been changed.  This commit
implements a check for the version being used, and includes the
header as is appropriate.

Special thanks to Hu.

Mantis-Bug: https://obsproject.com/mantis/view.php?id=966

Gentoo-Bug: https://bugs.gentoo.org/627520

Closes jp9000/obs-studio#1018

Closes jp9000/obs-studio#1021

UI: Add missing option to context menu

Use the Qt standard buttons in the source properties dialog to make the
UI consistent.  Also remove the right alignment of the button box to
allow Qt to align standard buttons on the left side of the dialog.

Closes jp9000/obs-studio#1013

Add 'Advanced Audio Properties' option to context menu over empty area
of the Mixer's pane.

Allows the ability to hide/unhide sources in the mixer that the user
doesn't care about or doesn't necessarily want to see (such as video
sources that have audio but don't have any audio playing).  If all
sources are hidden, the user can right-click the mixer's empty area and
choose "unhide all" via a context menu.

Closes jp9000/obs-studio#1002