guile-gnome, devel branch added

[David Pirotte]

Hello,

As discussed on irc, I've added a devel branch to the guile-gnome git repo.  
This
is good [practice] anyway, but as some of the patches I already submited and  
the
ones that I will submit from now on are not compatible with guile-1.8, we can 
also
use that branch to get rid of any guile-1.8 related fancies...

Cheers,
David