Also uses new min/max/invalid widget display

- Updated to use RCChannelWidget
- Removed attitude control widgets
- Previous calibration values now shown when not actively calibrating

Without this, when you go to airframe config and the current config is
Simulation it will not be selected. Hence you won’t know what the
current config is.

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.