Added Real State netcode/display

Added a real state in addition to the raw measurement, state estimate,
and additional information data that gets sent from the sensor server to
the display server.

Real State is drawn as a green circle and, as usual, is determined on
the sensor server before being sent to the display server. Actual file
parsing to retrieve a meaninful real state is not yet implemented,
currently only a list of one object at (0,0) is sent at each time stage.

Also: A few minor adjustments were made to the Display Server state
drawer, making measurement circles slightly smaller and priortising blue
circles (state estimate) on top of yellow circle (additional info)
rather than vice versa. Green dots (real state) are priortised to be
drawn over everything but measurement data (which is small enough to
draw over over circles).