Closes jp9000/obs-studio#1030

This is to prevent confusion with video_thread in
libobs/media-io/video-io.c, which is used exclusively for video
encoding/output.  Also prevents confusion in the profiler log data.

CI: Update Travis script to target OSX 10.10+

Closes jp9000/obs-studio#1056

Closes jp9000/obs-studio#1054

Log Windows 10 Gaming Features (Game Mode)

enc-amf: Version 2.2.4

Updates the plugin to work better with the AMF Runtime version 1.4.6.0, which removed some experimental properties.

UI: Fix Pulse Audio not loading saved device

libobs/util: Fix Windows 10 revision detection

UI: Disallow pasting duplicates of sources with DO_NOT_DUPLICATE

Fixes an issue where the log could have "Could not find service" with an
empty service name when opening properties.

Since OSX 10.10 is now the officially supported minimum OS version on
Mac, update the CI script.

This commit prevents users from being able to use the "Paste
(Duplicate)" context menu option after copying a source that has the
OBS_SOURCE_DO_NOT_DUPLICATE flag set. Though OBS would correctly paste
the source as a reference, it seems that this behavior was confusing
some users. This fixes Mantis Bug 1034.

This commit adds logging for Windows 10 Gaming features that may
negatively impact the performance of game capture, recording, or
streaming. This doesn't check Group Policy settings.

file-updater: fix crash due to network timeout

The new code in 3032535f would signal that the output has stopped to
the back-end and front-end, but the event used in the outputs themselves
to shut down the send thread would still be signaled, causing the next
connection to immediately stop as soon as it had started.  This fixes it
so that the event does not get signaled unless the thread is active.

This will help resolve incidents where users accidentally started or
stopped their stream without knowing what triggered it (usually from
hotkeys that were forgotten about).

Fixes a bug with reconnecting where the reconnecting would get stuck in
the "stopping" state.

Use unbuffered async mode by default, and when in unbuffered mode,
decouple audio/video so that audio plays as soon as it's received.

This is a workaround for decklink device drivers having unreliable
video/audio timestamps (audio/video sync drifting over time).  From
testing, it seems that the handling of video and audio is completely
separate in the driver; along with the timestamp calculations.  For
example, when the thread of the decklink audio callback is stalled, it
would cause the timestamps of the audio alone to go out of sync, which
indicates timestamps are calculated more or less on the spot independent
of what video is doing (which is how we replicated the issue fixed by
b63e4b05).  Because decklink drivers treats the audio and video as
essentially decoupled, we must also treat it as decoupled.  This is what
was causing video/audio to drift out of sync over time.

Decoupling the audio from the video causes the audio to be played right
when it's received rather than attempt to sync up to the video frames.
This is useful with certain async sources/devices when the audio/video
timestamps are not reliable.

Naturally because it plays audio right when it's received, this should
only be used when the async source is operating in unbuffered mode,
otherwise the video frame timing will be out of sync by the amount of
buffering the video currently has.

(This commit also modifies UI)

Instead of pinging Twitch every time the program starts up, only pings
for new servers when the ingests are actually being used, and when the
UI uses the auto-configuration dialog.

If ingests have not been cached when using the "Auto" server, it will
wait for 3 seconds max to query the Twitch ingest API.  If it takes
longer than 3 seconds or fails, it will defer to SF.  If ingests were
already cached, then it will use the existing cache immediately.

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.

If there is no network connection, OBS crashes after 5 minutes idling
with following crash:

*** longjmp causes uninitialized stack frame ***: obs terminated
======= Backtrace: =========
/lib64/libc.so.6(+0x6f1e3)[0x7f8f95f901e3]
/lib64/libc.so.6(__fortify_fail+0x37)[0x7f8f96018ba7]
/lib64/libc.so.6(+0xf7add)[0x7f8f96018add]
/lib64/libc.so.6(__longjmp_chk+0x29)[0x7f8f96018a39]
/usr/lib64/libcurl.so.4(+0xa5d5)[0x7f8f979b75d5]
/lib64/libpthread.so.0(+0x10e30)[0x7f8f962cae30]
/lib64/libc.so.6(__poll+0x2d)[0x7f8f95fff46d]
/usr/lib64/libglib-2.0.so.0(+0x4a64c)[0x7f8f91b5564c]
/usr/lib64/libglib-2.0.so.0(g_main_context_iteration+0x2c)[0x7f8f91b5575c]
/usr/lib64/libQt5Core.so.5(_ZN20QEventDispatcherGlib13processEventsE6QFlagsIN10QEventLoop17ProcessEventsFlagEE+0x5f)[0x7f8f9706c1ff]
/usr/lib64/libQt5Core.so.5(_ZN10QEventLoop4execE6QFlagsINS_17ProcessEventsFlagEE+0xfa)[0x7f8f9701defa]
/usr/lib64/libQt5Core.so.5(_ZN16QCoreApplication4execEv+0x9c)[0x7f8f970258fc]
obs(main+0x5ac)[0x4773dc]
/lib64/libc.so.6(__libc_start_main+0xf0)[0x7f8f95f41700]
obs(_start+0x29)[0x478389]

Internet search [1] revealed that this is a libcurl bug that can be worked
around by asking curl not to install signal handlers.

[1] https://stackoverflow.com/a/10755612

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.