[IS 12] Add Get/Set/Add/Remove/Find methods (#822)

* Fixed error reporting
* Added Set user label test
* Validate touchpoints
* Validate NcTouchpointNmos or NcTouchpointNmosChannelMapping depending on contextNamespace
* Sequence command JSON helper functions
* Build device model object tree when validating device model
* Check FindMembersByRole
* Recursively check each block's role paths
* find members by role test
* Find members by class id test
* GetMemberDescriptors test
* removed protocolVersion
* GetSequenceLength test
* Subscribe to all objects and test changing all user labels
* Add Class Manager method tests
* Added illegal command handle test
* IndexOutOfBounds test. WebSocket kept open test
* Updated comments and links to specification
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Co-authored-by: Gareth Sylvester-Bradley <garethsb@nvidia.com>
Co-authored-by: Gareth Sylvester-Bradley <31761158+garethsb@users.noreply.github.com>