[DVDPlayer/Subs] Save the subtitle number at the end of the OpenSubtitleStream() method.
Regardless of whether the subtitle has been opened successfully or not.
[GuiDialog/PlayerControls] Use CMediaSettings::Get().GetCurrentVideoSettings().m_SubtitleStream instead of g_application.m_pPlayer->GetSubtitle().
The latter one returns the maximal index if the current subtitle could not be opened. This yields wrong info about the subtitle.
[rbp/omxplayer] Simplify clock handling

In OMXClock we have an almost complete copy of DVDClock, so just use DVDClock directly.

The passing through of CDVDClock functions from OMXClock is hopefully temporary,
as I think clock manipulation is better handled from OMXPlayer than audio/video players.
Merge pull request #2833 from popcornmix/simplify_clock

[rbp/omxplayer] Simplify clock handling
[rbp/omxplayer] Add plumbing for audio GetCacheTotal
[rbp/omxplayer] OMX spec says we can transition from execute to idle
[rbp/omxplayer] Workaround for audio_mixer is not required

We have similar code in command line omxplayer, and that has never had this
workaround. I've been running with it removed for some weeks with no problems.

I believe it was working around a bug elsewhere that is no longer present.
[rbp/omxplayer] Add calls for stepping and retreiving the clock adjustment
[rbp/omxplayer] Use OMXPlaySpeed for pause/resume
[rbp/omxplayer] dispmanx now handles negative rectangles correctly so adjustment not required
[Python] Adds an optional parameter "sound" to Dialog::notification to allow a silent notification
Merge pull request #2836 from popcornmix/tidyups

[rbp/omxplayer] Some code tidy ups
Fix build after #3836
Merge pull request #2841 from popcornmix/fix_tidyups

Fix build after #3836
[FIX] add CFavouritesDirectory to ATV/iOS build targets
Merge pull request #2825 from ace20022/sub_fixes

[Fix/Subtitles] Fix wrong indices of erroneous subtitles.
Merge pull request #2842 from Fice/xcode_favdir

[FIX] add CFavouritesDirectory to ATV/iOS build targets
droid: fix libplist not loading due to missing symbols

We can hook up proper iconv support for libxml2 if it proves necessary, though
it has native routines for common conversions, and really shouldn't be
necessary for us.
depends: libxml2 doesn't depend on libiconv anymore
depends: help cmake find a few more build tools

This should fix linux build