deepzoom-tile: Attempt to prevent orphaned worker processes

Author: bgilbert

examples/deepzoom/deepzoom-tile.py

@@ -30,6 +30,7 @@
 class TileWorker(Process):
     def __init__(self, queue, slide, tile_size, overlap):
         Process.__init__(self, name='TileWorker')
+        self.daemon = True
         self._queue = queue
         self._slide = slide
         self._tile_size = tile_size