Play selection respects the selectionEnd point
[[ Bug 13063 ]] Fixed first part of bug 13063 (i.e. setting startTime to the correct point)
[[ Bug 13064 ]] playSelection respects start/end point. However a delay in pause appears when EndTimeChanged is called too often
Removed unused code
Merge remote-tracking branch 'upstream/develop' into bugfix-13063
Merge remote-tracking branch 'upstream/develop' into bugfix-13063
Shift+play starts playback from the correct starting point, put (sometimes) plays for some ms after the finishing point
fixed the crash
[[ Bug 13063 ]] Fix shift+play click issues (was due to incorrect handling of doubledown).
[[ Bugfix 13064 ]] Improved the delay issue when clicking pause (not fixed yet)
Added bugfix note for bug 13109
[[ Bug 13109 ]] Added comments
[[ Bug 13063 ]] Added bugfix note
[[ Bugfix 13063 ]] Added comments
Merge remote-tracking branch 'upstream/develop' into bugfix-13064

Conflicts:
	engine/src/mac-av-player.mm
Make sure loop property does not break
Merge remote-tracking branch 'panos/bugfix-13063' into bugfix-13063
Merge branch 'bugfix-13063' into develop
Merge remote-tracking branch 'panos/bugfix-13109' into bugfix-13109
Merge branch 'bugfix-13109' into develop