remove unused LinuxTimezone.h include
settings: fix timezone-related settings visibility and default values
settings: fix loading of platform-dependent settings definition files
settings: allow appliance.xml to overwrite runtime-dependent visibility conditions and default values
[rbp/omxplayer] Support planar float format audio directly

The update to ffmpeg1.2 has produced a significant performance hit on the Pi when decoding multichannel audio without passthrough.
This is because (most) audio codecs now output planar floating point, rather than interleaved S16 samples.
OpenMax/GPU can handle interleaved S16 samples directly, whereas the floating point planar samples get converted with swr_convert.
This is a slow operation, and a quick profile showed it to be taking about 150MHz of ARM CPU when using 6 channel audio.

I've added support on GPU for a new floating point planar format in audio_decode component.
This PR makes this format also supported for sending audio to the GPU.
The GPU now also handles the 6->8 channel padding so the UpMix() function is no longer required,
which may improve performance compared to pre-ffpeg1.2 version.

This PR requires recent GPU firmware. (384946 or later).
vdpau: fix segfault caused by uninitialized member
[rbp/omxplayer] Merge with current dvdplayer

To make spotting differences between omxplayer and dvdplayer easier in the future,
this is a pretty slavish copy, including dvdplayer's whitespace and header file includes.
You now get a pretty clean diff between dvdplayer.cpp/dvdplayer.h and omxplayer.cpp/omxplayer.h
Merge pull request #2796 from Montellese/settings_initialization_fixes

settings: initialization fixes
Merge pull request #2815 from FernetMenta/vdpaufix

vdpau: fix segfault caused by uninitialized member
[osx] changed, move videoplayer.usevda into darwin_osx.xml and nuke a vda dyload define
Merge pull request #2814 from popcornmix/audio_float_planar

[rbp/omxplayer] Support planar float format audio directly
Merge pull request #2798 from popcornmix/merge_dvdplayer

[rbp/omxplayer] Merge with current dvdplayer