Add support for new libcec method, PowerOnScreensaver
fixed, gas-preprocessor MUST see -arch switch or it will not self-configure for the proper arch
updated, gas-preprocessor.pl from https://github.com/mansr/gas-preprocessor
Add missing thread names, improve existing thread names

This extends on the work of PR #2323.

Since thread names are limited to 15 characters, we reduced the length of the name (removing starting C, get rid of spaces, remove trailing Thread, ...) where it made sense.

```
xbmc02:~ # pstree -p 715
xbmc.bin(715)-+-{EPGUpdater}(798)
              |-{EventServer}(790)
              |-{PeripheralBus}(778)
              |-{PeripheralBus}(779)
              |-{PVRAddon}(800)
              |-{PVRAddon}(932)
              |-{PVRGUIInfo}(933)
              |-{PVRManager}(799)
              |-{SoftAE}(777)
              |-{TCPServer}(791)
              |-{XBPython}(783)
              |-{XBPython}(784)
              |-{XBPython}(786)
              |-{XBPython}(787)
              |-{XBPython}(955)
              |-{XBPython}(972)
              `-{xbmc.bin}(792)
```

I would like to see more specific names for XBPython, PeripheralBus and PVRAddon. And also get rid of the remaining xbmc.bin thread name.
Merge pull request #2541 from dagwieers/pthread_setname2

Add missing thread names, improve existing thread names
Merge pull request #2012 from jmarcet/master

Add new Built-In function to control attached CEC device
GUIEpgGridContainer: validate scroll offsets as well as they are used to calculate rendered blocks
GUIEpgGridContainer: don't select first item if hoveing mouse over empty block
GUIEpgGridContainer: don't react on clicking channel list - might change it to select currently playing programme - this need some thinking
GUIEpgGridContainer: add panning gesture
GUIControlGroupList: add panning gesture