obs-studio: 0.13.1 -> 0.14.2

The biggest change is that since 0.14.0 it now has support for ALSA
sound input, so this also adds the ALSA library to the dependencies.

URL for upstream changes in 0.14.2:

https://github.com/jp9000/obs-studio/releases/tag/0.14.2

URL for upstream changes in 0.14.0 and 0.14.1:

https://github.com/jp9000/obs-studio/releases/tag/0.14.1

Changes for 0.13.3 and 0.13.4 were only Windows-related hotfixes, the
URLs are:

https://github.com/jp9000/obs-studio/releases/tag/0.13.3
https://github.com/jp9000/obs-studio/releases/tag/0.13.4

Upstream changes for 0.13.2:

 * Fixed an issue where certain devices (elgato/lgp/hdpvr) could have
   stuttering audio
 * Changed lossless recording quality to use .avi with uncompressed PCM
   audio data
 * Made it so that linux window capture does not display red when it
   can't capture, instead it now becomes transparent

URL: https://github.com/jp9000/obs-studio/releases/tag/0.13.2



Built and tested successfully on my machine.

Cc: @jb55
Reported-by: @rikai
Signed-off-by: aszlig <aszlig@redmoonstudios.org>