Implement initial version of listing cookbooks through the API

:fork_and_knife:

The API can list cookbooks via /v1/cookbooks.

* The default number of cookbooks returned is 10
* The max number of cookbooks returned is 100
* The cookbooks are sorted alphabetically

Adds JBuilder and an initial skeleton Cookbook model.

http://docs.opscode.com/api_cookbooks_site.html#get