[videodb] fix seasons update query for mysql, which doesn't like SELECT subqueries on the same table
[cleanup] followup to f86b9d2884
[videodb] fix tvshow view for mysql by utilising a subview. Thanks to @sccplg
Merge pull request #4988 from mkortstiege/threadmsgs

[cleanup] followup to f86b9d2884
Merge pull request #4985 from jmarshallnz/fix_mysql_query

[videodb] fix seasons update query for mysql
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
dvdplayer: observe pts counter overflow
dvdplayer: avoid short screen flicker caused by unnecessary reconfigure of renderer
vdpau: advanced settings for auto deinterlacing
player: fix rewind
OMXPlayer: some caching fixes for pvr
fix incorrect display of fps when dr kicks in
ActiveAE: slightly reduce buffer size
Revert "vdpau: comment some features that will be added later"

This reverts commit e00b4f65864d623ab4d2e9e5c06db138e661f1cf.