Overhaul Recipes.

* Use NFS by default. (Needs OSX help!)
* Use berkshelf instead of librarian-chef
* Use Ruby 2.0.0 as default
* Use standard box image with Ruby 2.0.0 and Ruby 1.9.3 pre-installed. (Box & initial DL is bigger, but it can be re-used)
* Use system wide RVM install to avoid user issues.
* Update generated README to reflect changes.