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
unistd.h is not needed
Move ASS_Shaper declaration to ass_shaper.h
Explicitly include ass_utils.h everywhere (and not config.h)
Fully fix compilation with MSVC/ICL

As before, this does not add any build system support:
a config.h file and a project must still be manually created
(or the compiler can be run manually instead of using a project).