TextArea: fix scrollbar content size calculation
DropCaps: fix palette regression

now that spans can inherit the palette of their parent, we need to explicitly make sure that PALETTE_INITIALS is not NULL or drop caps will inherit their parents palette when printing
OverheadText: fix multiline overhead text clobbering itself

fix overlap regression in text rendering to image
StringSizeing: fix a number of obscure bugs and oversights
GUIREC: fix another instance of unwanted drop caps
Journal: fix journal formatting

we were using the wrong "label" for the chapter and some newlines were missing
Video: cursorpos should be a point
VideoPlayback: simpler initialization code

all we are doing is filling the disp with balck...
Video: generalize screen clipping

before we were relying on SDL_SetClipRect(), but that only works for SDL
not only is this less code (because of dependance on SDL_Rect), but the OpenGL driver is now properly clipping its drawing