code: public JwwfServer bindServlet(ServletHolder servletHolder, String url) {
  		context.addServlet(servletHolder, url);
  		return this;
  	}
docs: <p>Binds ServletHolder to URL, this allows creation of REST APIs, etc</p>
  <p>PLUGINS: Plugin servlets should have url's like /__jwwf/myplugin/stuff</p>
  
  @param servletHolder Servlet holder
  @param url           URL to bind servlet to
  @return This JwwfServer