Added checkCanEditGroupApp to access.py.
Group Applications can now only be edited if they are either rejected or still in need of review.
Also fixed a bug in checkIsMyEntity.
Patch by: Lennard de Rijk
Reviewed by: to-be-reviewed
Benjamin Niemann <pink at odahoda dot de>: Main developer of Python target.
Clinton Roy <clinton.roy at gmail dot com>: AST templates and runtime.