Multiple parents for class5 in my test ontology.
paths_to_root brought from API
Added class in toy ontology. Class 7 with no attributes.
Test for path to root.
In class test parse ontology only once.
A cycle in the test ontology. For testing path to root.
Test multiple paths (multiple inheritance) for path to root.

sq
Path to root implemented also for cycles.
Fixed test for custom properties on check for RDFS label.