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

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

Adjust colors
Remove unused image