CLIENTS SHOULD NEVER CALL THIS METHOD FOR DAY TO DAY USE!
A subclass may override this method to implement redirection. Subclasses which have no need to do redirection may choose not to override this default implementation, which does nothing. For example, if a subclass wishes to write output to a file or is part of a testing harness, there may be no meaning to redirection.
Framework users who want to redirect should use a construction like RequestCycle.get().setRequestTarget(new RedirectRequestTarget(...));
or setResponsePage(new RedirectPage(...));
@param url The URL to redirect to