add builtin to set GUI Language
GUILabelControl support highlight/selection, and show cursor at same time.
[gui] added colordiffuse attribute on texture definition
demuxer ffmpeg: move m_streams into a map, drop MAX_STREAMS
dvdplayer: move extradata cleanup to CDVDDemuxStream destructor
dvdplayer: keep temporary stream pointer in ffmpeg AddStream
dvdplayer: keep ffmpeg demuxer indexes in continous order
demuxer ffmpeg: handle pmt changes
GUIWindowPVR: don't spawn dedicated thread just to invalidate channel items every 5 seconds. Instead run CStopWatch when activating channel window, check if 5 seconds elapsed and then inavlidate window and reset watch.
GUIEpgGridContainer: split Render() into Process() / Render()
GUIEpgGridContainer: get rid of GetRulerCacheOffsets() method which is just duplicated GetProgrammeCacheOffsets()
GUIEpgGridContainer: get rid of unused now (and never should be used) m_renderTime
GUIEpgGridContainer: fix memory freeing for ruler items
GUIEpgGridContainer: fix memory freeing for programme items
GUIListItemLayout: SetWidth() / SetHeight() - mark invalid only when new size is different from old one
Curl move header list into read state to support double state
Fix: now mp4 file on internet url can be played by dvdplayer by double session support of cache.
Increase USB and CEC rescan interval to 5 seconds

In one of my investigations to see why XBMC performance is so bad (even when idle) I found one of the threads (in my case PeripheralBusCEC) scan a big sysfs tree recursively. On the 1Ghz AppleTV 1 device this would be about 2% of the CPU *every* second. For the USB thread we luckily have Udev events, but for CEC it is using sysfs polling which is quite expensive. It would be better to make use of Udev as well for CEC (where available) however 5 seconds should be fine for everyone.

In my own builds I even brought it down to 30 seconds. Which means 29 seconds of reduced CPU usage.

The CEC polling probably should be more restricted to specific sysfs sections, or preferably use Udev as well, when available.

PS XBMC needs a special idle-state where it can turn down these expensive threads to make sure hardware can go into deeper sleep states. Especially for devices that doesn't do suspend for various reasons this is a requirement. (The ATV1 device for instance gets warm even when idle) If we can combine display-sleep with low-power states and a less expensive main-loop, that would be already quite an improvement without needing a complete refactoring of the code.
Use different names for USB/CEC and Udev related threads

While debugging some rescanning issues, it helped to distinguish the different PeripheralBus threads. Since there is a limit to thread names, I had to make sure the name fitted into 15 characters.

This is part of a series of PRs: #2323 and #2541

Before:
```
xbmc.bin-+-{EPGUpdater}
         |-{EventServer}
         |-2*[{PVRClient}]
         |-{PVRGUIInfo}
         |-{PVRManager}
         |-2*{PeripheralBus}            <-
         |-{SoftAE}
         |-{TCPServer}
         |-5*[{XBPython}]
         `-8*[{xbmc.bin}]
```

After:
```
xbmc.bin-+-{EPGUpdater}
         |-{EventServer}
         |-2*[{PVRClient}]
         |-{PVRGUIInfo}
         |-{PVRManager}
         |-{PeripBusCEC}                <-
         |-{PeripBusUSBUdev}            <-
         |-{SoftAE}
         |-{TCPServer}
         |-5*[{XBPython}]
         `-8*[{xbmc.bin}]
```
added ActivateScreensaver to builtin functions