Handle conflicting \t time intervals
Handle conflicting \t time intervals

If end <= start for a time interval specification, set end to the end of
the event.  VSFilter handles it like that, too.

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