#7 quad display stops

[Anonymous]

When drawing quads the drawing of the quad stops
when the last char has finished drawing on a real
machine. This only matters when the chars have different
start points relative to the start of the char bitmaps. If a
char starts later than the the last char o2em draws too
much, if it starts earlier o2em draws too little because
there is a wrap around to the next bitmap.

This feature will be used by KTAA in the future, but I
don't know any other game which uses it.

[Nobody/Anonymous]

Test program for quad cut off