- Update tfs-scenario.clab.yml

- update commands.txt

- Add dc-2-dc-l3-service.json descriptor

- Add topology.json descriptor

- Add directory tfs-descriptors

- Updated commands

- updated install command

- Added useful commands

- Added ContainerLab exercise

- Updated Netconf/OpenConfig descriptor files
- Normalized variable names in OpenConfigDriver
- Minor code cleanup

- Minor code cleanup

- Corrected Constraint definitions

- Restored execute permissions

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

- updated methods to properly retrieve/store connectivity services

- updated default IP address
- corrected error retrieval message

- migrated from DEFAULT_CONTEXT_UUID to DEFAULT_CONTEXT_NAME
- migrated from DEFAULT_TOPOLOGY_UUID to DEFAULT_TOPOLOGY_NAME
- migrated from INTERDOMAIN_TOPOLOGY_UUID to INTERDOMAIN_TOPOLOGY_NAME

- corrected run_test scripts

- integrated command files
- moved unused command listings to separate folders
- polished data files
- cleaned up TAPI show topology script and context database
- added TFS descriptor files

- added MockOSM package

- added basic Netconf/OpenConfig server

- updated tapi_app to plot topologies

- updated TAPI exercise