added solid color vectors; basic PAL8, 4x2-vector video (as in

Command & Conquer) looks great now; also added compressed codebook
support, but files using these (Lands of Lore) are not correct yet


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@2344 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b