Reuse of Rules of Association

[ratem]

Maybe a "central" repository of rules of association would be interesting, so that decorators and resources could reuse them. Should check the impact of it in configurator

[ratem]

Just implemented (08/19/2011) for Resources. Doing the same for Decorators is a bit more complex, since Configurator calls decorators' @classmethods to check if association is possible with a given object.