[mapserver-dev] graphics branch merge

[thomas bonfort]

I've updated http://trac.osgeo.org/mapserver/wiki/UnifyingTheRenderingInterfaces
with a couple of notes on the common rgba pixel format that will be
used by the plugin renderers (except for GD), to prepare for
integration with the raster handling code.

The graphics branch has been modified so the cairo and opengl code is
disabled by default, so it should compile without the need for those
libs.

Could we have a vote on wether I can merge this branch back into trunk
so further development on the plugin renderers can take place there?

tks,

thomas