Merge branch 'develop'

src/com/github/uiautomatorstub/AutomatorServiceImpl.java

@@ -68,6 +68,7 @@ static void setAsVerticalList(UiScrollable obj) {
      */
     @Override
     public String ping() {
+        new UiObject(new UiSelector()).exists();  // here we call the method just for checking if the UiAutomationService is ok, else it will throw IllegalStateException.
         return "pong";
     }