Bring vagrant-berkshelf up-to-par with the changes we've made in other projects:

1. Remove activesupport
2. Remove `autoload`
3. Use `require_relative` where possible
4. Remove JSON gem dependency
5. Remove unused dependencies
Don't install doc/guard dependencies on Traivs
Fix Thorfile and load order
Merge branch 'master' into cleanup

Conflicts:
	Thorfile
	vagrant-berkshelf.gemspec
fix scoping of GEM_PKG constant in Thorfile
place "doc" group of gems in proper groups
Merge pull request #62 from RiotGames/cleanup

Bring vagrant-berkshelf up-to-par with the changes we've made in other projects