http://dev.smartleaf.com/permissioning
That includes a git repository which can be cloned with
$ git clone http://dev.smartleaf.com/permissioning/demoapp/.git
(which copies in all the revision control information as well
as the or just inspected at
http://dev.smartleaf.com/permissioning/demoapp/
Core permissioning code --- which will be the guts of the
future plugin --- is at
http://dev.smartleaf.com/permissioning/demoapp/lib/
Have fun with it!
rst