Fronts admin: use configs & restyle

* Present user with the list of config'd fronts, then load all collections for the chosen config.
* Stack the collections vertically, to visually maintain their order within the config.
* Show more collections than was previously possible.

![tool](https://f.cloud.github.com/assets/1147913/1089754/9d1e0226-1649-11e3-837f-80a244e049b1.png)