[Cleanup] Remove not working stereo to mono split mode/setting.

Conflicts:
	xbmc/video/dialogs/GUIDialogAudioSubtitleSettings.cpp
[pvr] fix wrong printf format mismatch
dvdplayer: fix flushing message queue
Merge pull request #5027 from ace20022/rem_stereo_to_mono

[Cleanup] Remove broken stereo to mono split mode/setting.
Merge pull request #5405 from xhaggi/pvr-fix-printf-format-mismatch

[pvr] fix wrong printf format mismatch
Merge pull request #5406 from FernetMenta/msg

dvdplayer: fix flushing message queue
omxplayer: Reset codec on flush to stop a stale timestamp from being returned
[rbp] Hardware accelerated resampling

This replaces the format conversion, up/down mixing and resampling code from ActiveAE with a GPU accelerated version.
Should significantly reduce CPU when using paplayer or dvdplayer.

Requires updated firmware
[rbp/omxplayer] When opening a stream don't try to update gui so often
[ffmpeg] Speed up wtv index creation

The index creation is O(N^2) with number of entries (typically thousands).
On a Pi this can take more than 60 seconds to execute for a recording of a few hours.

By replacing with an O(N) loop, this takes virtually zero time
adds GetTvShowSeasons
move AddSeason() public.
adds GetArt function to (video) scraper, allowing art to be fetched given the video identifier.
refresh season art if a new season is found that isn't recorded in the database yet. Fixes #14339
REMOVEME: updated thetvdb.com scraper to support art updates
[omx] Report decoded image name
logging: Add microsecond timer to log messages
videoplayer: adapt lateness detection and dropping to buffering
video player: present correct pts to user for a/v sync (after buffering in renderer)
[hifiberry] Hack: force it to be recognised as IEC958 capable to enable passthrough options