Adds --enable-theora/--enable-vorbis/--enable-ogg to configure
   If compiled WITHOUT --enable-theora, native VP3 decoder is used
patch by (Nilesh Bansal <nileshbansal gmail com>)


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@3975 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b