##
new slider()

    s = new slider(length,start,end,interval,title)

A slider is created with five parameter: its length (in pixels), its numerical start and end values with the step interval, and the title. After creation it can be moved around, turned from horizontal to vertical (by shift-clicking the top border), and assigned a value, either by dragging the central square, or by clicking in the rest of the slider. Both operations will trigger the exection of the "move" and "stop" functions, assigned by the slider methods "setMoveFunc()" and "setStopFunc()".