Moved contact helpers in to simple ContactService.
Dropped no longer used `IContactInformation.is_user`.
Moved ContactInfo SortHelpers in to a separate class.
UserListing: Queries directly the ogds table, instead us using intern contactinfo helpers.
Pyflakes cleanup: removed no longer used imports and contactinfo instances.
Transitioncontroller: Dropped no longer used helper method `_is_issuer_inbox_group_user`.
Dropped no longer used cachekey methods.
Finally dropped the contact_information utility.
Pathbar: use current adminunits label instead of the current orgunits one.
Fix task creation in some tests, which now really need an issuer and a responsible.
Added is_inboxgroup_agency_active property also to the NullOrgUnit.
Skip tasktemplates tests.

Because the tasktemplate modul is not used in productive mode anywhere.
OuSelector viewlet tests: use ftw.builder to create test objects.