[droid] Enable external player support
In threads spawned within python the PyContext was never used. In those cases the releasing/acquiring of the Gil was simply skipped. Therefore scripts that looped over 'sleep' from a python created thread (a typical pattern in python services) would block all other python threads forever.
DVDAudioCodecFFmpeg: Convert unknown audio formats to float.

As of FFmpeg-1.1, some decoders started to output planar audio.
This fixes track ticket 13944.
Merge pull request #2059 from mcrosson/android-feature-external_player

[droid] External Player Support
Merge pull request #2115 from jimfcarroll/fix-14005

Fix for 14005. GIL wasn't managed correctly in python spawned threads
[droid] fixes #14014, bump libass version and package it
[IOS] - fix build after 6095130a0a441fdf61fa9ba1d1432ece3f5bc6a4
fixed: Missing build dep for libtiff-dev to the Linux/Ubuntu README docs
[touched] - revert unwanted submodule downgrade
Merge pull request #2117 from aballier/unknownaudioout

DVDAudioCodecFFmpeg: Convert unknown audio formats to float.
Merge remote-tracking branch 'origin/master' into android-tegra2