Dont disable target / anti-taget on navball when going ~0 m/s

[jkool702]

The title says it all. I understand why somethings are disabled at very slow speeds, since the directions of some stuff (like prograde and retrograde) can move quickly at slow relative speeds. the direction of the target cant. ironically enough, at 0 m/s relative velocity the target icon it not moving AT ALL, and thus there is no reason to disable it. Having these enabled for slow relative speeds would make docking a lot easier for me.