Add TODO

Add some future functions to develop
Modified some methods in WebClient

Change "sendPost/Get" methods in WebClient to "saveRequestToFile";
Modify related methods in Core and Connection classes.
Add HelperLauncher and HelperFactory

Add:
public interface HelperFactory - The factory to build connections and
cores;
public class HelperLauncher - The helper launcher contains a static
method to launch the helper.