Navigation wizard

There are enough little details to take care of to ensure good navigation that I will make a wizard for setting up the configuration (for multirotors at least).  The main thing this will do right now

 - force testing of the failsafe condition before advancing.  FlightStatus.ControlMode makes this nice and easy now
 - enable the appropriate modules and reboot
 - enable INSOutdoor mode
 - upload reasonable defaults for some of the navigation settings

I'm not sure if this will be an entirely new plugin or just a new set of pages in the setupwizard.  I think to reuse a lot of the abstraction the setupwizard created it will need to be in the same plugin :(