On an unloaded rotator, this fixes the rapid relay toggling without
needing to implement debouncing.
An additional configuration validation should probably be added: the
rotator rotates in azimuth about 6 deg per second. If the control loop
speed is too slow or the controller angle tolerance is small enough,
then the controller will never be able settle (imagine that the loop
interval is 1 second. That means the rotator will move approximately 6
degrees every loop iteration, so it will always overshoot.
There's not really any analogous concept for azimuth. This is for a
specific piece of hardware, so there's no real point in making it more
generic. This is respected at the 180 degree point as well, for
software that can handle flipped rotation configurations.
This doesn't currently play well with the elevation offset setting,
which should be applied after this clamping operation. Either this
needs to be moved to the API layer or (more appropriately) the input
range validation needs to move in the controller.
