fate: simplify vp8 rules
Make fate vp8 test cover emu_edge cases
Originally committed as revision 26134 to svn://svn.ffmpeg.org/ffmpeg/trunk
fate: move some groups of related tests to their own files
This moves some groups of tests for single codecs to separate files,and adds shorthands for running all tests in a group.
Originally committed as revision 24697 to svn://svn.ffmpeg.org/ffmpeg/trunk