Visualiser: Adding Flightgear as a visualisor for local simulators

This Task enables dune running on a developers machine to output simulated state messages to Flightgear for inspection. 

Later features for sending control inputs from flightgear back into dune will be added. 

Note: The intended usecase here is where FlightGears internal simulator (FDM) is disabled, and we are running a simulation in dune.