Solidify param handling

Fix retransmit

Also move default component ID into data model

Fixed race issues in config upload, tested to be reliable now - board startup scripts now need the other half of testing

Instantiate a PX4 config view in PX4 mode from start, since boards with just the bootloader (or no working telemetry) cannot be flashed else.

Migration to single parameter widget; ignore RC updates on unmapped channels 

don't process updates to unmapped rc channels when we're not in
calibration mode

send RC params to the known correct component ID

workaround problem where QVariant param values arrive as QString