allow the boot-time recording state to be configured
only process events on state transitions. Simplifies logic and debugging.
support regular Split 2s
allow menu enter/exit in 5-key mode
match betaflight with 5-Key OSD which requires an "enter" key
Allows control of 2-key and 5-key OSD menus and recording start/stop
OSD is disabled while in the RunCam menu but reinstated on exit
add arming checks to prevent arming while the OSD menu is enabled
Andy Piper
Andrew Tridgell