cubicweb-collaboration #3583049 expected reach [validation pending]

The feature should allow the following to work fully, or at least unimpaired:

* all 7 pylos-based applications (private)
* pafi (private)
* simulagora

This is a stringent stress-test, but imho worthwhile.
Prior experience with security containers, including:

* "exotic" complex & irregular security rules
* exotic multi-container, nested-containers,
subgraph-sharing containers,

should be incorporated.

priorityimportant
typetask
done in0.1.0
load3.000
load left0.000
closed by<not specified>