Fix url_name_args problems in user and group views. Add tests.
Merge pull request #929 from normanjaeckel/UrlNameArgs

Fix url_name_args problems in user and group views. Add tests.
Fixed #921 (Check THANKS URL for jQuery UI Nested Sortable)
Fixed #919 (Permission problem in agenda)
Updated EN po files.
Fixed #918 (Search does not work for guest users)
Fixed comments in pull request.
Fixed search-bar position.