AE: add settings to enable ac3 transcode and upmix via ac3 transcoding
ActiveAE: implement settings for ac3 transcode and upmix
AE: rename setting speaker configuration
Merge pull request #4025 from FernetMenta/audiopage

AE: add settings for ac3 transcode and ac3 upmix
fixed: Only force cache for video else it may cause a thread-storm
Merge pull request #4027 from arnova/file_cache_not_for_all_fix

fixed: Only force cache for video else it may cause a thread-storm
changed: Enable multicache for mkv files (fixes #13841)
changed: We should always check for multistream when caching
Merge pull request #3963 from arnova/mkv_multi_cache

changed: Enable multicache for mkv files (fixes #13841)
videoplayer: adapt lateness detection and dropping to buffering
video player: present correct pts to user for a/v sync (after buffering in renderer)
videoplayer: some rework and documentation
renderer: bump buffers to 5
videoplayer: update frametime, it might change due to fps detection
videoplayer: give streams with invalid fps a chance for fps detection
dvdplayer: allow rewinding at end of stream, do a seek after rewind
X11: ditch SDL for video and window events
X11: Add xbmc icon
X11: add SDL joystick until we have a better solution
X11: factor out code handling device reset notification