[GRASS5] 5.7: experimental RPM available

Hi,

finally I succeeded to write a script generating GRASS 5.7 RPMs.
A first test packages can be downloaded here:

http://mpa.itc.it/markus/grass57/rpms/

If it's quality is acceptable (of the RPM package), I'll
enable weekly auto-generation.

Let me know,
suggestions are welcome,

Markus