pvr: Added API function GetRecordingEdl

This extends the PVR API with the function GetRecordingEdl
to retrieve edit decision lists from the PVR addon.

In addition, DVDPlayer's EDL class has been adapted to read the EDL
from the backend when starting playback of a recordings.
dvdplayer: Allow multithread decoding for hi10p content by default

This allows decoding of some hi10p material on e.g. AMD Fusion with
both cores at the max. This introduces a new advancedsetting named
disablehi10pmultithreading to disable hi10p decoded multithreaded.
changed: Add rule for selecting remote (or non-local) items for player selection rules
Stay on safe side, use only one header file.
Other header is located at xbmc/linux/ and seem to be more accurate.
Add CTL_BUTTON_CLEAR control message for generic keyboard to clear text.
[release] version bump to 13.0 alpha2 as we start new merge window.
Add compilationartist property to AudioLibrary.GetArtists
Remove unused variable initialization
pvr: Write playCount in WriteClientRecordingInfo
pvr: Read recording's last played position from field in PVR_RECORDING
pvr: Cosmetics
addons: Add Announce function and register addons for announcements

This allows addons to receive announcements and react properly on
all kind of events and system state transitions.

For example pvr addons might want to close and reopen their backend
connections when the system goes to or resumes from standby.
addons: Add WakeOnLan function

WakeOnLan allows addons to send a wol magic packet.

This can be used for example in pvr addons to wake up a pvr backend.
[rbp] Fix for audiotoggledigital on Pi.

Pi only has two audio output modes so the three way toggle gets stuck. This fix corresponds to Pi specific settings code:
https://github.com/xbmc/xbmc/blob/master/xbmc/settings/GUISettings.cpp#L458
guilib: simplify BindToTexture and support any unit

All stages we support are in order after texture 0
gl: add missing alpha setup for texture stages
gl: avoid using explicit texture, use bound texture
opengl/d3d: add support for limited color levels (16-235)
intents: Add a java class for listening to intent broadcasts
intents: hook up a JNI_OnLoad for finding our java functions

This should be extended to do lots more, so that we can quickly add java code
and access it from native, without the mess that is jni.