vp9/x86: simplify a few mc inits.
lavfi/vidstabdetect,vidstabtransform: update to vid.stab 0.98

In particular:
* set default value for accuracy to 15 (max)
* add zoomspeed for dynamic zoom (optzoom=2)
* make camera path optimization algorithm configurable
* update optzoom documenation in code to use new localmotions calculation function commandline arguments
* add debug option in vidstabtransform

Signed-off-by: Georg Martius <martius@mis.mpg.de>
Signed-off-by: Stefano Sabatini <stefasab@gmail.com>
configure: add version check for pkg libraries, and use it for vidstab

Also fix trac ticket #3296.

Signed-off-by: Georg Martius <martius@mis.mpg.de>
Signed-off-by: Stefano Sabatini <stefasab@gmail.com>
lavfi/vidstabtransform: apply various cosmetical nits
vp9/x86: 16x16 iadst_idct, idct_iadst and iadst_iadst (ssse3+avx).

Sample timings on ped1080p.webm (of the ssse3 functions):
iadst_idct:  4672 -> 1175 cycles
idct_iadst:  4736 -> 1263 cycles
iadst_iadst: 4924 -> 1438 cycles
Total decoding time changed from 6.565s to 6.413s.
avcodec/huffyuv: add a field that represents the number of symbols

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec/huffyuvenc: init bps from pixel descriptor

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
libavcodec/huffyuv: >8 bit support

This adds only yuv420p10, others are trivial to add after this commit
and will be added in a subsequent commit.
Currently the implementation is not optimized, optimizations will be
added later

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>