settings: split requirement conditions from <visible> conditions into new <requirement> tag
[win32] update VS project files
settings: implement new "visible" dependency for dynamically showing/hiding settings
[osx/ios/atv2] - sync xcode project
[rbp/omxplayer] Fix uninitialised variable that can lose audio packet

The uninitialised variable meant the first run through Decode goes through the non-passthrough path (when passthrough)
and so doesn't get correctly submitted and is discarded
[rbp] Fix type of transform parameter to match latest firmware
Merge pull request #3071 from popcornmix/uninit_audio

[rbp/omxplayer] Fix uninitialised variable that can lose audio packet
music: fix crash when calling CTagLoaderTagLib::Load() through IMusicInfoTagLoader::Load() (introduced by d0a5a97e0c6c7831db382dfdc3e8650ff500acb9)

The class definition of CTagLoaderTagLib was completely screwed up. It is used
as if it was derived from IMusicInfoTagLoader but it actually wasn't.
Furthermore the signature of the CTagLoaderTagLib::Load() method was not
completely identical to the pure virtual method definition in
IMusicInfoTagLoader (std::string instead of CStdString) so it's a miracle this
didn't blow into our faces earlier.
Merge pull request #3076 from Montellese/tagloader_fix

music: fix crash when calling CTagLoaderTagLib::Load() through IMusicInfoTagLoader::Load()
Merge pull request #3073 from popcornmix/transform_type

[rbp] Fix type of transform parameter to match latest firmware
[rbp] Switch from libshairport to libshairplay for airplay
Merge pull request #3077 from popcornmix/libshairplay

[rbp] Switch from libshairport to libshairplay for airplay
Merge pull request #3060 from Montellese/settings_visible_dependency

settings: dynamically show/hide settings
[RFC] Use ffmpeg to determine whether a gif is animated or not.
[RFC] Store a flag "isAnimated" in the picture's PictureInfoTag.
[RFC] Store a flag "isAnimated" in the fileitem's property map.
[RFC] Play gifs in a repeating video playlist. This does not affect slideshows.