[Etoys] text rendering

Alan and everybody,

I pushed two change sets that deal with some inefficiency in text rendering. Some are already known issues around the recalculation of some properties and some are a bit or tidying up of code. Most notably, True Type font rendering is much faster now.

I still think the use of True Type should be somewhat limited, but for making splash screen or that kind of thing, it should be ok to use it if it doesn't change color of characters in a text (as much), and don't other stuff overlap with text (as much).

-- Yoshiki