Changes:

- Add telemetry, client and subscription database and remove temporal databases
- Simplify restconf namespace endpoints
- Modify client functions in api main
- Modify subscription functions in api main
- Modify telemetry functions in api main
- Move functions in api to specific mapper and realizer functions
- Create workflow for monitoring in main
- Create aggregate_monitoring function in mapper
- Create get metrics function in realizer
- Move functions for retrieving simap telemetry to tfs_connector function
- Add new paths for simap telemetry retrieval and for ietf networks
- Move telemetry cache into config.py
- Modifications in postman collections for testing