Improve fullname matching
Improve fullname matching

Only match outline fonts and take slant and weight into consideration.
This matches all font faces which have at least the slant/weight that is
requested. This fixes issue 23; however, corner cases can be constructed
in which wrong fonts will be matched, if multiple slant/weight variants
of the same font exist, but that is very unlikely in practice.

tgoyne/libass,tgoyne/libass,stps/libass,pigoz/libass-ct,rhlee/libass,pigoz/libass-ct,rhlee/libass,pigoz/libass-ct,astiob/libass,stps/libass,stps/libass,vault/libass,mwgoldsmith/libass,mwgoldsmith/libass,ShiftMediaProject/libass,xbmc/libass,libass/libass,blinkseb/libass,libass/libass,MrSmile/libass,Distrotech/libass,MrSmile/libass,asimonov-im/libass,tgoyne/libass,torque/libass,Akemi/libass,mwgoldsmith/libass,Akemi/libass,rhlee/libass,blinkseb/libass,Distrotech/libass,sanyaade-g2g-repos/libass,richardpl/libass,sanyaade-g2g-repos/libass,ShiftMediaProject/libass,grigorig/libass,Distrotech/libass,torque/libass,xbmc/libass,astiob/libass,grigorig/libass,richardpl/libass,blinkseb/libass,sanyaade-g2g-repos/libass,torque/libass,vault/libass,asimonov-im/libass,richardpl/libass,Akemi/libass