Added Frozen Blocs Configuration.

The Planning Box was partially refactored in some parts by me (and also Romain) these lasts months, this commit was the initial  ones.


The tests and documentation update will come soon.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@15883 20353a03-c40f-0410-a6d1-a30d3c3de9de