Remove unnecessary entries from Berksfile
Pin Berkshelf to ~> 2.0.10
Use generic devops email address
Clean up Ruby style as per Rubocop

* Single quotes over double quotes for non-interpolated strings
* Whitespace
* Ruby 1.9 style hashes
Update nginx config to match latest from kibana cookbook

Maintains basic auth, however
Switch to file-based install for Kibana; we don't need full source
Remove unneeded or deprecated config from Vagrantfile
Use Chef Omnibus instead of shell script