Added an "unknown" weather icon for when I get "valid" data and no icon

Break apart string of classes into their own files as all in one file became unwieldy
Expose Airspace data in a QML ready format
Split global Airspace from AirMap (Only now I figured out the reason for the pure virtual root classes)
Refactored a bunch of things to make it consistent and/or obvious

All settings wired and persistent
Cleanup non Airmap builds

Move all airmap related stuff to its own directory

Move  MAV_PARAM_TYPE to  MAV_PARAM_EXT_TYPE as we're now using the proper MAVLink version.

Eliminated flight widget "states"
Define flight widget top margin (plugin options)

Adjust colors
Remove unused image