Merge pull request #247 from idonasch/leak_fix

fix for issue #245 'Memory leak and CPU hog in addEffect()'

Author: julianschill

src/led_effect.py

@@ -158,6 +158,9 @@ def addEffect(self, effect):
                                                 self._pollStepper,
                                                 self.reactor.NOW)
 
+        if effect in self.effects:
+            self.effects.remove(effect)
+
         self.effects.append(effect)
 
     def _pollHeater(self, eventtime):