Revert tracing setup test (9004eb8c) in node_list_tuples

The node_list_tuples method is performance critical and can't afford to
do additional queries only for testing the setup. Therefore, the new
test is removed there. It is, however, still done in tree_object_list.

Thanks Albert Cardona for the pointer.
Increase performance of tracing setup test

The tracing setup test functions now allow to optionally pass already
available class and relation maps. If available these are used instead
of new ones. Additionally, one can deactivate testing for the root class
instance.

Also for the test in tree_object_list, no Project model instance is
explicitely fetched anymore for the permission test. This saves one more
query (according to the SQL log).
Test tracing setup before tracing tool is activated
Merge branch 'fix-tracing-setup-test'

Conflicts:
	django/applications/catmaid/control/node.py