refactor(policy): integrate monitoring protobuf updates

See merge request teraflow-h2020/controller!167

Slice component

See merge request teraflow-h2020/controller!176

- clean-up old files
- update requirements.in

- Added timestamp to logs
- Implemented DeleteSlice method
- Enhanced create/update slice logic

Multiple changes in Context component:

See merge request teraflow-h2020/controller!175

Common:
- Extended context proto with 2 methods: UnsetService and UnsetSlice

Context component:
- Added timestamp to logs
- Added methods UnsetService and UnsetSlice to Context client
- Implemented methods UnsetService and UnsetSlice in Context servicer
- Resolved conflict between service and slice entities with constraints and configrules

PathComp component improvements

See merge request teraflow-h2020/controller!174

Merge branch 'feat/pathcomp-component-frontend' of https://gitlab.com/teraflow-h2020/controller into feat/pathcomp-component

Merge branch 'feat/pathcomp-component-backend' of https://gitlab.com/teraflow-h2020/controller into feat/pathcomp-component

- Added timestamp to logs
- Improved algorithm execution logs
- Added basic support for multi-layer path computation
- Improved KDisjointPath Algorithm with basic multi-layer support
- Minor improvements in backend request composition
- Removed unneeded code for unitary tests
- Added OLS-flavoured unitary test scenario

- Increased number of supported topology nodes.
- To be improved with dynamic memory.

Context/Device/Service/PathComp/tests/WebUI component fixes and improvements

See merge request teraflow-h2020/controller!173

- renamed device type OPTICAL_LINE_SYSTEM to OPEN_LINE_SYSTEM

Common:
- renamed device type OPTICAL_LINE_SYSTEM to OPEN_LINE_SYSTEM
- added DATACENTER and EMULATED_DATACENTER device types.

Context:
- modified service constraints for test object to use nomenclature "metric[unit]"
- corrected ConstraintModel dump methods

Device:
- uncommented dump methods in database ContextModel and TopologyModel

OFC'22 / OECCPSC'22 tests:
- renamed device type OPTICAL_LINE_SYSTEM to OPEN_LINE_SYSTEM

WebUI:
OFC'22 / OECCPSC'22 tests:
- renamed device type OPTICAL_LINE_SYSTEM to OPEN_LINE_SYSTEM

- added object factory method for emulated datacenters

- Fixed instantiation parameters in Dockerfile

Common:
- Added missing object factory methods for constraints

Context:
- Adapted unitary tests to new constraint object factory methods

Service:
- Adapted unitary tests to new constraint object factory methods

PathComp-Backend:
- Deactivated health probes since it causes problems in backend REST server

PathComp-Frontend:
- Correct unitary test constraints for SP algorithm
- Adapted unitary tests to new constraint object factory methods
- Fixed instantiation of ShortestPath and KDisjointPath Algorithms
- Ignore unknown constraints in Algorithm request composition

Frontend:
- added show logs script
- improved config settings to get address and port of the backend
- improved logging of _Algorithm
- implemented KDisjointPath logic

Backend:
- added show logs script

- Fix CI/CD pipeline

- correct unitary test constraints for SP algorithm

- Fix CI/CD pipeline
- Correct log argument to make it screen-only
- Remove old data files
- Activate health probes

Adding friendly traces for debugging purposes in the process of parsing the context JSON

- Added support of the GET method to check status of PathComp
-Added support for showing logs via either Screen (stdout) or defined Log file

- Added deploy script used for tests