how much is this specific to the cmf? would it maybe make sense to just give a brief overview in our doc and otherwise contribute to http://sonata-project.org/bundles/cache/master/doc/index.html? or http://sonata-project.org/bundles/block/master/doc/index.html? not sure what integration happens on which layer here.

at least we should identify for the reader what are cmf specific things and what are general sonata block/cache features.