* Radio Master Bandit 5-Way Joystick: first draft
Untested on genuine hardware
* "Okay" moves to next frame, even when canned message disabled
* Refactor to allow easier customization
* Implement feedback from testing
* guard toggleGPS()
* show "Shutting down.." screen
* split adhoc ping alert onto two lines
* Don't block while waiting for shutdown
Was preventing the alert from showing
* More compatible
Changed a RADIOMASTER_900_BANDIT_NANO to DISPLAY_FLIP_SCREEN that is responsible for flipping the OLED screen for better compatible with other devices.
* Update variant.h Radiomaster
Remove a un-used SCREEN_ROTATE and added DISPLAY_FLIP_SCREEN
