Move plane/stride calculation out of the individual pixfmt converters
Support different image height/buffer height during pixfmt conversions
Do not send dwControlFlags for only the MPEG2 Chroma Location info

MPEG2 chroma location is the default for 4:2:0, and the information
is as such not really useful, and not worth the extra reconnection cycle.
Update ffmpeg
Update ffmpeg for DTS fix
Check the decoder exists before trying to decode
Disable DXVA2 Extended Format support for the overlay mixer

Overlay mixer responds badly to these flags, resulting in a black screen in some cases.
Update ffmpeg
Link against the debug runtime when building MSVC debug ffmpeg
dxva2: disable vc1/wmv on Intel GPUs

The latest Intel drivers have started to expose the VC-1 decoder GUID, however
the decoder is still broken and crashes or produces a broken image.
Include wmcodecdsp.h and remove any duplicate GUID definitions
Support VC1/WMV3 Image codecs
Update opencore-amr libraries
Update Opus to 1.1rc2
Update libspeex to a recent build
Update build instructions for thirdparty libs
Update ffmpeg

Also re-enable --disable-doc, which was broken for a while.
Make sure side-data is merged until a proper solution is implemented
Disable the HQ Deint option on XP, to reduce user confusion
Update ffmpeg for matroska enhancements