Restore menu overview

The menu overview has been removed. Because of this the module has become unusable on its own. It is no longer possible to create menus, or edit any other than the first created menu. The only way this works is by installing a range of other modules which are not listed as dependencies, basically by installing the entire Paddle distribution.

I suggest to restore this vital functionality, the alterations which are required only for the Paddle distribution should be done in the install profile using menu_alter().