timeshift: minor mod to htsp to flush output buffer on skip
(cherry picked from commit c862269c622579629a2ca80c3bfe521a751cb8ba)
timeshift: add return to live function to HTSP
(cherry picked from commit 404316f08f0b5c30b94dd4c5983c2359f3a51de2)
Fix #1444 - dvr: ensure that DVR entries are not removed when EPG is updated

previously an overlapping (replacement) event could result in the DVR
entry being completely removed. This will now ensure that the original
entry is left in place (with just info and times).

It will also try and re-match with an EPG entry as and when it can.
(cherry picked from commit a0a7539a731c6e84b8e0a3a95b1c1655a12515c7)
Fix #1643 - dvb: close dvr device on each re-tune
(cherry picked from commit 55ed28cb53307f77c7c767cd6f87f56b15951bcd)
dvb: fix problems with dvb satconf processing and storage
(cherry picked from commit aac905c18488e90ebb467de9c3e2eece4f1fd5ac)
dvr: ensure unlinked entry updates are properly handled

previously it updated things that were already linked and also on
different channels entirely.
(cherry picked from commit 6c6e0541be21fc574241c3c244f2b28c24db2021)
dvr: another minor improvement to epg/dvr relinking

Realised that we don't need to update things that are no longer
scheduled (i.e. complete).
(cherry picked from commit ab7302ec99587576f76d22d03bd6853769868432)
dvb: fix mistake in dvr close commit (wasn't restarting thread)
(cherry picked from commit 1c9e85b326874b7a6178fd73c28feae0aed3318b)
Fix #1657 - timeshift: add constant length qualifier to avoid warning on some arch's
(cherry picked from commit 819b8c83948becde08a6fdfad0228fd7607693ca)
Fix #1660 - dvb: stop constant updating of dvb mux configuration files
(cherry picked from commit 07cdfdaf6af06ae08a779ccc9082a517757c6fd3)
Fix #1643 - dvb: alter the way we handle dvb tuning

This ensures that demux filters are not installed until after tuning
is locked. This should resolve most stale data issues.
(cherry picked from commit ddc466c1bfa7405563a68a662114f5a3659d7cb5)
gtimer: increased resolution of the gtimer system.

This is needed to resolve a dvb tuner deadlock issued caused by my
re-jigging of the tuning setup code.
(cherry picked from commit 4f2f68a4b65a9ab5ecce80c867b9d7813de665a3)
Issue #1666 - dvb: rework the adapter tuning to stop possible deadlock
(cherry picked from commit 75856cd5a6ae53cd7103140d06dfd0b2f77ff55f)
xmltv: fixed parsing of star-rating
build: disable libav by default for 3.4
cwc: syslog: move some log messages to debug
(cherry picked from commit 484b3f6d23971144fa538ae9172a772a6bbd307a)