The forward method passes control to another run mode and returns its
output. This is equivalent to calling '$self->$other_runmode', except that
the CGI::Application manpage's internal value of the current run mode is
updated.

This means that calling '$self->get_current_runmode' after calling
'forward' will return the name of the new run mode. This is useful for
modules that depend on the name of the current run mode such as the
CGI::Application::Plugin::AnyTemplate manpage.