Implement support for multi-sensor group operation

[jhodapp]

Summary

Allow for multiple sensor groups (e.g. different sensor group for different rooms/contexts)

Feature specifics

• Refactor DB schema model such that a group of sensor readings can be associated with a specific context (e.g. room name such as "Living Room" vs "Bedroom") -> This needs intentional design consideration and discussion
• Redesign dashboard to display multiple sensor groups (e.g. select a room to display)

Not included

• This does not include updating the Edge client nor the ambi_mock_client -> this work is captured in separate issue under each respective repository
  • Note: you may want to do part of this work before or in parallel to this issue