currently the only way to retrieve the path of the item associated with an authorizable is to check if the
principal obtained through Authorizable#getPrincipal() is an ItemBasedPrincipal.
having a getPath method would provide a convenient shortcut and would in addition allow
to determine of there is really an item associated with a authorizable that is accessible for the editing
session (which is not necessarily the case for ItemBasedPrincipal#getPath