Singletrack UI slow if the rotor controller is slow to respond

[bjorgan]

Issue at LA1K station: The rotor controller often times out and is slow to respond, so the UI hangs since we always wait for the response of the last command before issuing a new rotor position. Ends up screwing up the doppler shift correction as well.

(Mentioned in #103 (comment))

[bjorgan]

Mostly fixed in #109, still missing improvements to the status window.