Summary:
- added only one function for getting the total (in + out) vertex degree, it's required for the Ravelin use-case
- specific `degree_in` and `degree_out` functions can be added as necessary
- also fixed random_graph_generator bug (needed it for testing)
Reviewers: buda, mislav.bradac
Reviewed By: buda, mislav.bradac
Subscribers: pullbot
Differential Revision: https://phabricator.memgraph.io/D652
47c1cd6e3d