GeneratorVideo: set type of data to char
Frame: indent with spaces
Add SWIG interface for frame classes
Pixel: fix init from AVPixelFormat

Correctly set BigEndian, Alpha, and Planar flags.
VideoTransform: fix fill plane data pointers

* Error for subsampling YUV420 in init when fill in cumulSrcOffset.
* Use FFmpeg function av_image_fill_pointers instead of manage it in our
code.
* Remove unecessary _srcOffsets and _dstOffsets.
Generators: fix frameBuffer when fill it from a specific _inputFrame