ISIS-839: renaming examples and archetypes

* quickstart_wicket_restful_jdo -> todoapp
* simple_wicket_restful_jdo -> simpleapp
ISIS-839: renaming archetype directories.
ISIS-574: bumping to Shiro v1.2.3.
ISIS-840: fix perm group stuff for IsisPermission

Also (commented out) updates to the todoapp example.