def onboot():
    """Chained call from :meth:`IWebApp.startapp`. Implementation 
        can chain this onboot() call further down to other framwork /
        application plugins.

        While building a web application, this method can be used to configure 
        url route-mapping by calling :meth:`add_view` or by parsing a mapper
        file. In any case, when this method returns, route-mapping must be
        compiled and cached for resolving request's view-callables.
        """
