Marquee creation support

[gdamore]

Marquee text creation now is a rather tiresome task. It would be nice to support creating marquees and banners easily, using just the glyphs taken from a property, then applying one of several kinds of styles.

Possible Styles:

* solid color (taken from a color list)
* flashing colors (again from color list) -- all characters have the same color, which rotates at a frequency
*  bounding box - move with a velocity inside the bounding box, bouncing off edges
* scroll -- scrolling text -- with given X & Y scroll velocity
* alternating colors -- each character gets a different style  (with flashing colors, can choose forward or reverse)
* waving -- letters form a wave using a box 3 characters high -- this can also roll forwards or back

I imagine these could be combined with attributes, allowing for quite a list of options.