Right now if you press the arrows in the ArrowDiscWidget of the Navigational Floatitem it will only move once. If the allow is pressed longer than pressThreshold = 300ms the map should continue to move a further step every 300ms until the mouse is released.Once released the map should stop moving.

This behaviour should be implemented for all four directions: Up, Down, Right and Left. While keeping the button pressed the styling of the buttons should reflect that state.