This patch brings all of the previous work together and starts to
actually parse and decode frame information. Currently it only parses
the uncompressed header data (section 6.2 of the spec).
The VP9 specification requires a special decoding process to parse a
lot of the data read from a frame, so this BitStream wrapper implements
that behavior. These processes are defined in section 9 of the
VP9 spec.
This commit initializes the LibVideo library and implements parsing
basic Matroska container files. Currently, it will only parse audio
and video tracks.
