ADR on reading/writing discrete values in DS using REST

Per Kamakura planning meeting (Nov 21) - an ADR is needed to address the fact that there is no way to model a remote procedure call way of calling in a device service.

Original need stems from support objet type in both Set/Get command issue #3754 on edgex-go.

How to support devices/sensors that have a functional protocol API.
- Example: ONVIF – camera has a SOAP based web service; function call that takes multiple parameters
- Tricky when input is a complex object (again ONVIF)
- REST vs SOAP or GRPC calls
- Modeling we have is not up to the task to support these more complex function calls
- Kong does support GRPC style of protocol
- RFID/LLRP DS need is similar
Impact: Command and device services

Discuss in architecture group about how to start and where this work originates