Complement functional tests

Develop and adapt functional test as needed :
_deletion and creation of OTS interfaces done
_func tests for connections on unidir ports of ROADM to be done
_test for PCE reverse path with different logical connection point names ?
De-prioritized since corrections on topo manangement shall be done before

Improve existing functional test to be able to restore the controller or node datastores as they were at the begining of the functional test suite.