paplayer: fix caching of streams into AE
Fixed: prevent the querystring from being stripped if no sub streams are found in a m3u8 playlist.
[remote keymapping] map the BACK button to Back in fullscreen (rather than smallstepback in fullscreenvideo and lockpreset in visualisation)
RFC: [addons] install dependencies prior to installing the real thing. Fixes #13918
Revert PR#3231 and make "visualisation as screensaver" behave as having fullscreen toggled (so it won't trigger screensaver state at all)
Merge pull request #3822 from basrieter/m3u8_qs_fix

Fixed: don't cut of the query string to determine the basepath in M3U8 files
Merge pull request #3881 from jmarshallnz/back_means_back

Map the BACK button to Back in fullscreen
Merge pull request #3778 from herrnst/vis-is-no-ss

Revert PR#3231 and make "visualisation as screensaver" behave as having fullscreen manually toggled (so it won't trigger screensaver state at all)
Merge pull request #3882 from jmarshallnz/deps_first_please

RFC: [addons] install dependencies prior to installing the real thing.
Merge pull request #3886 from FernetMenta/aefixes

AE: fixes
Merge pull request #3814 from FernetMenta/paplayer

paplayer: fix caching of streams into AE
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