Fix crazy VSFilter behavior for \move tag
Fix crazy VSFilter behavior for \move tag

Fixes issue 90 (both cases).

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