Initial implementation of the FaceTec interop

[MOZGIII]

The goals of this PR:

• introduce the API client for the FaceTec SDK
• implement the robonode server and the logic for interop with the FaceTec Server according to the bioauth v1 plan B architectural diagram
• provide an example for the error handling patterns and error structure (looking forward to discussing this)
• provide an example of the code standard for the inline documentation requirements
• roughly illustrate the required amount of unit tests (though the more - the better)

To do:

• unit tests
  • facetec-api-client
  • robonode-client
  • robonode-server
    • [ ] logic - will be addressed separately, see Implement proper unit tests for robonode logic #4
    • [ ] handlers - will be addressed separately, see Implement proper unit tests for robonode logic #4
• integration tests
  • [ ] robonode client to server - will be addressed separately, see Implement proper end-to-end tests for robonode client to robonode server #5
  • [ ] facetec client to facetec server - will be addressed separately, see Implement integration test suite for facetec-api-client #6
• [ ] real implementation of the Verifier and Signer traits at robonode-server - we'll address this after we introduce substrate
• [ ] sequence persistence (make it survive restarts) - tracked as Make robonode sequence generator persistent and use UUID as a prefix #7

[dmitrylavrenov]

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