Add AUTHORS file

Changes the OBS_FRONTEND_EVENT_SCENE_CHANGED event after transitioning
is complete rather than right when the user hits a scene change.

LGP devices are devices that induce anger in any sane developer because
they're prone to bad audio timestamps when using their decoded data
directly.  For that reason, add a hack that smooths the timestamps
within a large threshold to prevent audio skipping.

On windows, when a source has only audio (no video) yet is marked as
capable of both video and audio, it would be programmed to expect a
video frame to synchronize with.  This fixes that potential issue by
detecting whether any video is actually playing or not.

When kaspersky is installed on windows 7, FindWindowEx will fail to find
any windows due to apparently being blocked by kaspersky, so detect when
that happens, and fall back to GetWindow instead if it does.

Allows saving replays programmatically without having to use hotkeys.

Uses a custom library for checking whether game capture is active and
for killing stray obs processes

Changed the build scripts around so that it operates off of a different
directory structure

Similar to the OBS1 file where you can optionally get the signature if
available in the header (for auto-updating)

So many checkboxes were together almost senselessly.

This is mainly to give visual feedback to those affected by NVENC not
working with older driver versions. Currenlty obs fails silently which
could go unnoticed for users who are using hotkeys as well as confuse
users who are not trained to read their logs when issues occur.

Closes jp9000/obs-studio#788

rtmp-services: Update twitch ingests

Adds canadian ingest server.

Due to crashes being caused by hardware acceleration in the media source
on mac, disable hardware acceleration of the media source being on by
default for the time being.

In transitions, because the 'to' and 'from' are always rendered to
textures, the end result will always have premultiplied alpha.  This
would cause alpha to have blackish edges during transition, and cause
semi-transparent images to appear darker than they were supposed to.

To replicate, simply set the transparency of a source to 50%, then
transition between that scene and another scene.  The source will appear
to "pop" in and out unnaturally due to the premultiplied alpha effect of
the render targets.

To fix this, the solution is to simply convert premultiplied alpha to
straight alpha in the transition pixel shaders.

When the OBS signal is triggered for these widgets, the invokeMethod
could cause the thread to stall, which could make it wait much longer
than necessary to output audio data.  When that happens, it causes audio
monitoring to get backed up and get unnecessarily delayed, as well as
cause general audio buffering in libobs to increase unnecessarily.

A simple fix both in terms of preventing that stall and improving UI
performance is to not call invokeMethod to update the widget each time,
and then instead have those widgets update themselves via a timer at a
specific interval.

Adds audio monitoring selection to advanced audio properties, and adds
the ability to select the device in advanced settings.

(Note: This commit also modifies mac-capture and linux-pulseaudio)

This prevents outputs from being monitored, preventing a potential
feedback loop.

Adds functions to turn on audio monitoring to allow the user to hear
playback of an audio source over the user's speaker.  It can be set to
turn off monitoring and only output to stream, or it can be set to
output only to monitoring, or it can be set to both.

On windows, audio monitoring uses WASAPI.  Windows also is capable of
syncing the audio to the video according to when the video frame itself
was played.

On mac, it uses AudioQueue.

On linux, it's not currently implemented and won't do anything (to be
implemented).

Ensures audio has the source-local timestamp when used with audio
monitoring.

Ensures that the system always has a record of when the last video frame
was played.

Packs related controls together and makes a bit more room for more
advanced settings.

Closes jp9000/obs-studio#789

rtmp-services: Update twitch/hitbox ingest and youtube recommendations

Twitch added the following ingests:
- South America: Lima, Peru
- EU: Lisbon, Portugal
- South America: Medellin, Columbia
- EU: Milan, Italy
- NA: Mexico City

The following ingest server is no longer listed in hitbox'  API:
- US-East: Washington

YouTube does not list a requirement that states that only the main profile can be used.

CI: Unzip VLC quietly