Create a development environment using Vagrant/Chef.

Follow up on issue #1498 (closed).

There is still a few things not good in here, but this is a good moment to make a pull request to have feedback.

To install the dev environment, after installing virtual box and vagrant, just do:

$ gem install librarian
$ librarian-chef install
$ vagrant up

At this moment, I'm still stuck with some failing tests, probably due to charlock, and since I'm using NFS it's not going to work on windows machine.

Another point is probably to update the basebox to something sexier (maybe Ubuntu 12.04).