added test cases for token revocation based on a given user
corrected some test cases for access token revocation as subsequent requests to revoke an access token aren't authorized any more
added test cases for token revocation upon user deactivation
added test cases for token revocation upon user deactivation by user replacement
Merge pull request #179 from osiam/osng-467

Osng 467: integration tests for token revocation on user deactivation