- adapted all modules to not use views.ConfigurationView anymore
- removed templates that are not needed anymore
- no more implicit 'enabled' and 'get_status' functions in __init__.py files
- (more coherent/explicit use of Django functionality)
- Installing dbcommon-pgsql and not install dbcommon-mysql does not
ensure that PostgreSQL is selected as the database for the
application. Set a debconf value to force selection of PostgreSQL.
- Minor styling fixes.