Update Rubocop and fix new warnings

Fixes #175
Bump Berkshelf version
Use build-essential 2.0
Don't lock transitive dependency yum (just use yum-epel)
Fix lua (EXPORT -> export)

- Fixes #178
- Fixes #186
Fix service name in tests

- Fixes #198
Merge pull request #199 from opscode-cookbooks/sethvargo/bump_build

Bump build-essential to 2.0