Rename Item.sendState0 to Item.stateUpdated.

- Also added some documentation
- Resolves issue #15

eraser-base/src/main/jastadd/Item.jrag

@@ -235,35 +235,45 @@ aspect ItemHandling {
   public void ItemWithBooleanState.setState(boolean value, boolean shouldSendState) {
     if (isFrozen) { return; }
     set_state(value);
-    sendState0(shouldSendState);
+    stateUpdated(shouldSendState);
   }
 
   public void ItemWithStringState.setState(String value, boolean shouldSendState) {
     if (isFrozen) { return; }
     set_state(value);
-    sendState0(shouldSendState);
+    stateUpdated(shouldSendState);
   }
 
   public void ItemWithDoubleState.setState(double value, boolean shouldSendState) {
     if (isFrozen) { return; }
     set_state(value);
-    sendState0(shouldSendState);
+    stateUpdated(shouldSendState);
   }
 
   public void ColorItem.setState(TupleHSB value, boolean shouldSendState) {
     if (isFrozen) { return; }
     set_state(value);
-    sendState0(shouldSendState);
+    stateUpdated(shouldSendState);
   }
 
   public void DateTimeItem.setState(Date value, boolean shouldSendState) {
     if (isFrozen) { return; }
     set_state(value);
-    sendState0(shouldSendState);
-  }
-
-  //--- sendState0 ---
-  protected void Item.sendState0(boolean shouldSendState) {
+    stateUpdated(shouldSendState);
+  }
+
+  //--- stateUpdated ---
+  /**
+   * Called, whenever the state of an item is updated. Does various things including:
+   * <ul>
+   *   <li>Send the new state via MQTT</li>
+   *   <li>Send the new state to Influx DB</li>
+   *   <li>Notify the attached {@link ItemObserver}, if any</li>
+   *   <li>Update state of controlled items</li>
+   * </ul>
+   * @param shouldSendState whether to send the new state (currently affects MQTT and Influx)
+   */
+  protected void Item.stateUpdated(boolean shouldSendState) {
     if (shouldSendState) {
       try {
         // sendState() defined in MQTT aspect