[#1143] Also stop timer when call releaseExternalResources()

src/main/java/org/jboss/netty/handler/traffic/AbstractTrafficShapingHandler.java

@@ -479,6 +479,7 @@ public abstract class AbstractTrafficShapingHandler extends
         if (timeout != null) {
             timeout.cancel();
         }
+        timer.stop();
     }
 
     @Override

src/main/java/org/jboss/netty/handler/traffic/GlobalTrafficShapingHandler.java

@@ -51,7 +51,7 @@ import org.jboss.netty.util.Timer;
  * {@link OrderedMemoryAwareThreadPoolExecutor} or {@link MemoryAwareThreadPoolExecutor}).<br>
  * <tt>pipeline.addLast("GLOBAL_TRAFFIC_SHAPING", myHandler);</tt><br><br>
  * </li>
- * <li>When you shutdown your application, release all the external resources (except the timer internal itself)
+ * <li>When you shutdown your application, release all the external resources
  * by calling:<br>
  * <tt>myHandler.releaseExternalResources();</tt><br>
  * </li>