Fix sorting issues with QmlObjectListModel
Show airspaces in Plan View as well

An rather unfruitful attempt at consolidating Advisories and Airspaces (they are both arrays of Airspaces). No such luck as they vary wildly. In the end, I'm now exposing the restrictions (Polygons) directly (and inherently) instead of copying them.
Tweaked polygon overlay colors and borders.

Handled "airspace visible" state (not done)
Adjusted restriction map items color and opacity
Added/Updated icons for airspace traffic
Adjust colors for text over maps