[rbp/omxplayer] First attempt at decode to texture
[rbp/gui] Add switch between higher and lower quality textures

To save memory we default to 16bpp textures,
but provide a GUI option to increase that to 32bpp.
[rbp/gui] Add switch to remove GUI 720p limit
[rbp/omxplayer] Add caching of states to reduce number of round trip delays to GPU
Revert "[rbp/omxplayer] Add caching of states to reduce number of round trip delays to GPU"

This reverts commit 691cfc567895b6645d7052b292f44f557004059b.
 [rbp/omxplayer] Avoid clipping with amplification
[rbp/omxplayer] Add fixed latency mode for live streams
[rbp/omxplayer] Support multichannel PCM audio output over hdmi

Requires updated firmware (from next branch)
[rbp/omxplayer] Avoid marking non-monotonic timestamps as unknown

Following a single spurious timestamp that is in the future,
all subsequent timestamps will be marked unknown causing out of sync.
[rbp/omxplayer] Multichannel audio: add missing files
[Players] Avoid jumping volume to maximum after trickplay
For players that control volume, if the speed changes (e.g. with ff/rew) the volume gets reset to maximum.
This change sets it back to current value, although I question why it is being changed at all.
Do any players require muting during trickplay?