Revamp command messaging #281
Description
Following #120, we should revamp our command messaging. It should have the following properties:
- Commands should be handled and returned in FIFO order #367
- Add "notifications" to kernel commands #368
- Simplify command and stream types #369
- This is as opposed to specifying complete, over-the-wire command and reply types for each method.
- Convert internal stream types to JSON-RPC #464 was merged into this issue.