Transfer architecture; partial implementation

GameWindow:
-added utility class TransferBuffer to hold incoming/outcoming Aircraft
+visibility of methods prevents abuse
+one created per locationWaypoint, publically available
-Aircraft removed from the airspace due to completion are moved into the
buffer (out)
-added  checkTransfers()
+any Aircraft waiting in the in buffers are copied into the airspace
with a fresh FlightPlan from that waypoint
!the buffers will accumulate Aircraft unless cleared or polled

Demo:
-clears the out buffers of GameWindow instance

Multiplayer:
-halved distance of TransferBar
-polls "City of Rightson" buffer and pushes planes into the TransferBar
+clears other buffers
-Aircraft exiting the left of the TransferBar are shunted into the
"South Sea" buffer
!test logic randomly places Aircraft from the second Airspace into the
TransferBar
GUI tweaks

Increased colour depth of the warnings over departures when an Aircraft
is waiting