Add "busydialogdelayms" advanced setting.

Provides control over the delay until busy dialog is shown when starting
video playback.
Added a boolean condition to identify the Raspberry Pi platform (System.Platform.Linux.RaspberryPi)
remove old unused renderer files
Disable channel icon scan when icon path is empty

XBMC checks the icon path and terminates the scan early if no path is set. This commit causes the setting to respect that.
Show values of string settings with button controls
remove unload/reload of fonts when init/destroy window, as it's not needed anymore
add infolabel Player.Filename
CurlFile: request UTF-8 as preferable charset
CurlFile: don't set 'keep-alive' as cURL do this internally
Some web servers can't properly handle duplicated header value.
[GUIInfoManager] Add VideoPlayer.AudioLanguage infolabel.
[DVDPlayer] Set CMediaSettings::Get().GetCurrentVideoSettings().m_AudioStream on open/set.
revert 5fd167da1ebf407dcb4afa87d1a3bd5a6d66fedb
[Win32] resolution of namespace std:: conflict for bind()
add audio and subtitle language info to video osd if available
[release] version bump to 13.0 alpha10 as we start new merge window
Fix memory leak in SurfaceFlinger.

Call native_window_api_disconnect to free the memory used by OMX video decoder.
Or, there is memory leak in SurfaceFlinger after a stream playback is stopped.
[win32] Use more VC optimizations for important XBMC parts for 'Release' config
* Enable 'Full' code optimization
* Prefer speed over small size
* Allow any suitable inline function
* Enable Generate Intrinsic Functions
* Enable Function-Level Linking
* Enable 'Whole Program Optimization' for compiler, linker and lib task
* Explicitly enable linker optimization /OPT:REF and /OPT:ICF
[win32] Fix various linker warnings
[win32] Fix win32 VS debugging environment. No need anymore to copy dlls to Debug/Release dirs.
[Players] Avoid jumping volume to maximum after trickplay
For players that control volume, if the speed changes (e.g. with ff/rew) the volume gets reset to maximum.
This change sets it back to current value, although I question why it is being changed at all.
Do any players require muting during trickplay?