[BlueBream] merging bbkit into bluebream!

[Christophe Combelles]

Hi,

I've first worked in a branch to let bbkit depend on the ZTK
http://svn.zope.org/bbkit/branches/ccomb/

After that change, I realized we actually don't need bbkit anymore...
So I've merged it into the bluebream package:
http://svn.zope.org/bluebream/branches/ccomb-remove-bbkit/

It works and it is simpler for everything, because there is only one package to 
maintain and release. and the version list is very small now. Then we can 
consider adding other community packages such as z3c.form and others.

I've also added a way to choose the version of BlueBream when creating a 
project. That means, if a new version of BlueBream is released with changes only 
in the versions.cfg, we can create a new project with these new versions, 
without upgrading the bluebream package. It's still compatible with previous 
versions, and works the same way.

I've added a note on how to release bluebream now, which is not very different:
- just tag the bluebream package, and upload its versions.cfg.

If there is no objection I'll merge the changes into the trunk, and retire bbkit!

We will be able to release BlueBream 1.0 at the same time as the ZTK 1.0!

Christophe