Start adding alternate message streamers. Make algorithms less bad.

persontracking/lidar_cache.py

@@ -2,6 +2,7 @@ import rplidar
 from rplidar import RPLidar
 from threading import Thread
 from persontracking import algorithms
+import persontracking.lidar_tracker_pb2 as tracker_pb
 import zmq
 
 
@@ -52,8 +53,7 @@ class LidarCache():
 
     def fireGroupsChanged(self):
         # Send the updated groups to 0MQ socket.
-        # self._socket.send_multipart(["lidar_map", ...])
-        pass
+        self._socket.send_multipart(["lidar_map", tracker_pb.PointScan(points=[]).SerializeToString()])
 
     def stop_scanning(self):
         self.run = False