[atv2] - fix compile after reshuffle 16f276b
CoreAE: mixerunits input is the inputunits output

Not this still doesn't resolve all issues. We are still not
setting up a correct channel map for the output
[atv2] - fix learned remote buttons for fwd and rewind ios 6.1 (atv2 5.2) - apple changed the values for those for filling a gap in the enum i guess. Also those 2 buttons are repeatable - so handle them right for not firing 2 messages for one keypress (press, release)
[osx/ios] - adapted README.osx and README.ios for usage with new unified depends
[CA/AE] - make the devicelist change callback more robust - should fix crashes during shutdown on some system constellations (where removing the callback seems to also triggers the callback at the same time)
Remove duplicate Player.SeekBar entry in GUIInfoManager.cpp

Previous entry is L#177, 10 lines earlier
[Fix] ACTION_GESTURE_NOTIFY should not trigger video osd.
Merge pull request #2466 from ulion/fix_gesture_notify_action_on_fullscreen

[Fix] ACTION_GESTURE_NOTIFY should not trigger osd.
[Fix] slideshow swipe wrong direction detection.
FIX: [droid] volume up/down not working
Merge pull request #2469 from ulion/fix_slideshow_swipe_wrong_direction

[Fix] slideshow swipe wrong direction detection.
changed, assert(0) is nasty, this could just be a bad audio packet
Merge pull request #2470 from koying/fixdroidvolume

FIX: [droid] volume up/down not working
[osx/ios] - adapted readmes - building python module pil isn't needed anymore (will be handled by unified depends in the future - wip)
depends: fix pil build with zlib

Its "build system" is clueless, so rather than jumping through hoops to help
it find zlib, we'll just assume zlib as a hard dependency
depends: add pil to default depends, and add freetype as a dependency
depends: remove python pil helper scripts and docs, they've been moved to depends
depends: nuke old darwin depends
depends: nuke old android depends
depends: update android docs to point at unified depends