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
Render each event on a separate thread using pthreads
Dumb hack: check if fribidi is unsafe, and use a mutex if it is
We're also OK if fribidi has --with-glib
Generate tables for each thread