login: add link when using external auth to make it easier to login using oauth providers.

rhodecode/templates/base/base.mako

@@ -322,8 +322,9 b''
                     <div class="buttons">
                         <div class="register">
                         %if h.HasPermissionAny('hg.admin', 'hg.register.auto_activate', 'hg.register.manual_activate')():
-                         ${h.link_to(_("Don't have an account ?"),h.route_path('register'))}
+                         ${h.link_to(_("Don't have an account?"),h.route_path('register'))} <br/>
                         %endif
+                        ${h.link_to(_("Using external auth? Login here."),h.route_path('login'))}
                         </div>
                         <div class="submit">
                             ${h.submit('sign_in',_('Sign In'),class_="btn btn-small",tabindex=3)}