version 1.2.3

Changelog:
- FFmpeg/libav avresample support
- OpenGL ES2 support. Can build against Qt5 GLES2 version now
- XV support for Qt5
- more audio format support, e.g. sample format, channels.
- Fix H.264 decoding error for the beginning frames.
- Fix audio decoding error if packet should be decoded multiple times.
WMA audio.
- Save video captures to system Picture directory