* geis does not work with channels2 and never will be (it has to be python now)
* pytest
* rewrote cache system
* use username instead of pk for admin user in tests
* change get_restricted_data and get_projector_data to always use a list
* Add typings to all get_restricted_data and get_projector_data methods
* Replace CollectionElementList with a real list
* Fixed arguments of inform_deleted_data
* Moved CollectionElementCache to cache.py and refactored it
* Run tests with cache enabled (using fakeredis)
* Add caching support to users/group
* Add a function has_perm that works with the cache.
* Removed our session backend so other session backends (without the database) can be used
Also added the derective osPerms to check if the current user has permissions.
Removed old Django views and urls for user.
Created utils.views.APIView which should be used instead of the AjaxView.
Fixes: #1470Fixes: #1454
* seperate unittests and integration tests
* moved old tests in seperat folder 'old'
* created a testrunner that does not create a testdatabase, if only unittests are run
* wrote some unit- and integration tests as examples
* fixed user.get_short_name() to use the sort order from config
* fixed wrong url_pattern in the user app
