[GRASS-dev] Renaming G3d into Rast3d

[Soeren Gebbert]

Dear devs,
i just noticed that massive renaming in the G3d library is going on.
Nothing against to follow name convention, but it would be nice if
this kind of changes are discussed in the list first, so i can prepare
myself and my G3d dependent software for it.

I only noticed the changes because my vtk-grass-bridge is not working
anymore ... .

Best regards
Soeren