Added network interrupt callback for ffmpeg, plus various methods for setting/getting timeout
Added network interrupt callback for ffmpeg
Added QTAV_DEFAULT_NETWORK_TIMEOUT
Merge remote-tracking branch 'remotes/vcovito/vito_AVDemux2' into vito

Conflicts:
	src/QtAV/QtAV_Global.h
interrupt status init.
enable QtAV/FFmpeg runtime version check