* collorg.orm.relation.Relation is now JSON aware. Any set can now be
  dumped and loaded in JSON format using _cog_json_dumps and _cog_json_loads
  methods.
* Remove controller.web.WebController cog_ref_obj attribute.
* Fix #3 (empty comments).
* Fix #5 (to many comments displayed...).
* Group list template was kdjljdlkdjlk [sic].
* Remove some unfortunate tries/excepts in the ORM.
* Web interface improvement: CSS colored buttons.