cmd/alignment-netsender: create variable to put aligner into a controller override state

There should be a variable available to allow specification of a servo angle that would override the controller when set i.e. the servo would move to the servo angle and stay there until the variable is deleted. This might useful in cases where telemetry indicates the aligner is misbehaving. We can move the servo to the next best position i.e. 90 degrees.