[CinCVS] More Tracking

[Edouard Chalaron]

hSince we are talking about tracking and stabilisation, I will add an
extra layer: the mjpeg tools have a y4mstabilizer that is working nicely
for me.
However it needs a color sampling of 444 which may not be available to
everybody.
I use it before importing in Cinelerra.
Cheers
E