ass_parse: remove 2 unused variables

Fallout from the previous commits.
configure.ac: Treat DragonFly as the rest of BSDs
Fix integer overflow in FT_Outline
Merge pull request #116 from hadvaid/dragonfly

configure.ac: Treat DragonFly as the rest of BSDs
Merge pull request #119 from MrSmile/fix-drawing-overflow

Fix integer overflow in FT_Outline
Fix \fade(7-argument version) parse
Round ascender and descender like VSFilter