glyphlists (test 'em out)

[Lauris Kaplinski <lauris helixcode com>]

Hi!

I added test implementation of glyphlists and positioned glyphists to
gnome-print.

The idea:

Glyphlists can represent rich attributed text in device independent
way. I.e. they can encode:

* Glyphs
* Exact glyph positioning
* Relative glyph positioning
* Standard font advancements
* Letterspaces
* Kernings
* Colors
* Font changes

If done The Right Way, glyphlists should preserve as much device
independence, as possible - i.e. we usually use font advancement instead
of exact glyph positioning. Still exact placement can be used for complex
scripts.

For displaying glyphlists are "compiled" into positioned glyphlists, where
each glyph are given fixed position. GnomeFonts are replaced by
GnomeRFonts and only color attributes are carried on.

The implementation can be seen in gnome-canvas-hacktext (the amount of
code was enourmosly reduced due to them) and testprint4.c. The latter
shows very simple use of attributed (colored) text
lines. GnomeCanvasHacktext now displays quite nicely on gdk-canvas
(although I'm afraid that leaking memory as hell).

TODO:
- Find the best way to encode these (speed / memory / readability)
- Implement currentpoint push/pop for complex positioning
- Find opentype glyph attributes (width) that have to be encoded

Lauris