Add Berkshelf, RuboCop, Test Kitchen, etc.

* Config to test Ubuntu 12.04 & Debian 7.2
* RuboCop config to set code style expectations
* Minimal Berksfile
* Rakefile with handy test tasks
Add ChefSpec tests, use bleeding-edge ark

Need the bleeding edge ark so we have access to the ChefSpec matchers
that haven't landed in a released version yet.

Courtesy of that unreleased ark, some breaking changes to the LWRP:

* Add ark prefix_home to deal w/ ark changes
Add Travis CI style & unit testing
Add ServerSpec tests
Use a resource guard instead of vanilla Ruby

More Chef-like, and ensures the resource exists, even if it’s not
acted on
Merge pull request #9 from evertrue/use-guard

Use an `only_if` guard instead of vanilla Ruby
Merge pull request #7 from evertrue/add-tests

Add tests using RuboCop, Food Critic, ChefSpec, & Test Kitchen
Add all the badges!