PolicyAdd rpc replaced by PolicyAddService & PolicyAddDevice

- restructured component and separated it into "connector" and "gateway" subcomponents.
- arranged name typos in DLT proto file
- prepared component folders for dlt-connector component

- added missing dependency for unitary tests

- Corrected unitary test to execute pipeline

- corrected unitary test file for device component
- arranged clients used by optical centralized attack detector
- Minor corrections in unitary test of Context component
- corrected skeleton for unitary tests of Slice component

- Migrated to use new generic gRPC servicer and clients
- Migrated to use new settings framework
- Improved definition of unitary tests and solved some bugs
- Minor code formatting/styling

- added helper methods to object_factory

- Migrated to use new generic gRPC servicer and clients
- Migrated to use new settings framework
- Commented wrong/outdated unitary tests (to be coded)
- Minor code formatting/styling

- Migrated to use new generic Rest servicer
- Moved client declarations close to use places to prevent initialization locks
- Adaptations to comply with the new settings framework
- Updated unitary tests to use new generic Rest and gRPC servicers and clients
- Minor code styling/formatting

- Migrated to use new generic gRPC servicer
- Migrated to use new generic Rest servicer
- Migrated to use new settings framework
- Minor code formatting/styling

- Migrated to use new generic gRPC servicer
- Migrated to use new settings framework

- Migrated to use new generic gRPC servicer
- Migrated to use new generic Rest servicer
- Migrated to use new settings framework
- Migrated tests to use new generic servicers and mock's
- Extracted common unitary test functionalities into separate code files
- Minor code styling/formatting

- Migrated to use new generic gRPC servicer
- Migrated to use new generic Rest servicer
- Migrated to use new settings framework
- Migrated tests to use new generic servicers and mock's
- Solved bug with endpoint monitors' population (dupplicated sample types due to wrong key generation)
- Use Emulated driver when both driver and device type are not specified
- Separated unitary tests and execution scripts per device driver
- Extracted common unitary test functionalities into separate code files
- Minor code styling/formatting

- Migrated to use new generic gRPC servicer
- Migrated to use new generic Rest servicer
- Migrated to use new settings framework

- defined unified constants for all micro-services
- defined common settings getter methods
- defined generic gRPC servicer
- defined generic Rest servicer
- defined common MockServicer for Monitoring component
- removed old common/tests MockService class; to be replaced by new generic gRPC servicer
- minor code formatting/styling