- Pre-merge cleanup

- Added device type IP SDN Controller
- Added logic to split controllers and devices
- Controllers are onboarded first, then devices

- `common` > `tests` > `InMemoryObjectDatabase.py`: enhance log error reporting
- `common` > `tools` > `descriptor` > `Tools.py`: correct formatting of non-string resource_values in custom config rules in method `format_custom_config_rules()`
- `common` > `tools` > `service` > `GenericRestServer.py`: correct format of reported listen URL

- corrected parsing of slice descriptors

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

- solved issue parsing slice config rules

- new generic descriptor loader tool
- new scenario loader for automated tests

- added support for json-formatted custom config rules

- solved bug with JSON descripotor file load.