- Fixed unitary test launch scripts

- Fixing GitLab CI/CD pipeline
- Updated scripts to manually launch NBI tests

- Fixing GitLab CI/CD pipeline
- Updated script to manually launch IETF L2VPN test

- Updated unitary test launcher scripts

- Updated unitary test launcher scripts

- Implemented skeleton of plugin
- Added test scenario
- Added new requirements
- Extended MockContext to properly link/unlink topologies, services and slices to contexts

- Restored execute permissions

- Added/Updated headers
- Added script to update copyright headers

- removed unneeded comments from run_tests_locally*.sh in scripts folder
- minor improvement in report_coverage_all.sh
- added script to expose through the ingress controller the gRPC interfaces through the ingress controller for debug purposes

- monitoring/test_monitoring.py: provides a basic testing skeleton
- monitoring/requirements.in/.txt: updated with pytest
- monitoring/genproto.py: added instructions to import generated Python modules using "from . import ..." instead of "import ..."; otherwise, pytest and other possible modules doing imports might complain.
- monitoring/monitoring_server.py: packed start_server and stop_server functionaity to simplify test definition, minor formattings, bug resolutions and improvements in package import.
- monitoring/monitoring_client.py: minor formattings, bug resolutions, and improvements in package import.