Graphite module should work also when monitoring module is not installed. Hence the `MonitoringAwareController` which is the
base class for `ListController` and `MonitoringGraphController`should not use `Icinga\Module\Monitoring\Controller` as its
base class (use class `Icinga\Web\Controller` instead).
Add the required methods in `Icinga\Module\Monitoring\Controller` directly to `MonitoringGraphController`.
