Java2D renderer almost up to satisfying quality

[Jeremias Maerki <de...@jeremias-maerki.ch>]

I've just committed some changes which helps the Java2DRenderer narrow
the gap to the PDF and PS renderers. The remaining problems are:
- Font sizes are rounded down to the next integer when java.awt.Font
instances are instantiated.
- There's a coordinate system problem with block-containers which have
"fixed" positioning.

The metrics now practically match those we retrieve from the font files
ourselves. This results in almost matching output now between PDF, PS
and Java2D (print, TIFF, PNG). Not much left to do here. :-)

Jeremias Maerki