Multiple motion sensors bug

[BrnLng]

Hi! Needed to add multiple motions sensors and the code had a bug where only the last added sensor would work at the tkinter window. Just needed to add a param to the root.bind call for class TkMotionSensor(TkDevice) at tkgpio.py:

root.bind('', self._motion_detected**, add='+'**)

[wallysalami]

Sorry for keep you waiting! You are absolutely right. I'm going to fix it right now.