Update Development Tools

- Set Ruby Version to latest: 2.1.5
- Update ChefSpec
- Update Test-Kitchen
- Update ServerSpec spec_helper to work with latest.
- Remove Vagrant Plugins. They are no longer included in Vagrantfile.
Add Rubocop and update Travis-CI Config

- Add Rakefile
- Add Rubocop
- Fix Rubocop Warnings
- Update Travis-CI to use new Rakefile
Merge pull request #15 from pwelch/update_dev_tools

Update Dev Tools