BC break: remove 'controller' from route modification

This break makes [Action-Domain-Responder](https://github.com/pmjones/mvc-refinement) the primary idiom, instead of Model-View-Controller. Previously, the $route_callable would set both 'controller' and 'action' params in the route; now, it sets only 'action', and it is just a copy of the route name.

You can regain the old MVC route modifications with this:

```php
<?php
    $router->setRouteCallable(function ($route) {
        $action = $route->name;
        if (! $action) {
            return;
        }

        $controller = null;
        $pos = strrpos($action, '.');
        if ($pos !== false) {
            $controller = substr($action, 0, $pos);
            $action = substr($action, $pos + 1);
        }

        if (! isset($route->values['controller'])) {
            $route->addValues(array('controller' => $controller));
        }

        if (! isset($route->values['action'])) {
            $route->addValues(array('action' => $action));
        }
    });
?>

typo here, `$action_class` doesn't exist, it's `$class`