Renamed FlightDataModel class to WaypointDataModel class. This
creates namespace for the PathSegmentDataModel class.
[To be squashed]: Fixed define name.
[UAVO]: Create static getNumInstances() method for each UAVO.
This makes getting the number of instances a little cleaner and
easier to use.
Added path segment descriptor to flight data model.
Created MapArc class and made waypointcurve a child class.

Conflicts:
	ground/gcs/src/plugins/opmap/modelmapproxy.h
Fixed missing include.