Add sample hiera configuration
Add note about the module cache
Don't let .DS_Store files break script/bootstrap

Fixes boxen/our-boxen#512

In particular, I have seen problems with the following hidden files that Mac creates:
- `.DS_Store`
- `.!59508!.DS_Store`
- `.!59554!.DS_Store`
Mention the default hiera configuration in README
Suggest some example hierarchies
Be explicit that puppet-module-data is important
Fix typo for ripienaar/puppet-module-data module
Fix for when is GNU sed installed in homebrew with --default-names
Update to puppet-nodejs 3.7.0
Add deep_merge to the Gemfile(.lock) and vendor it
Upgrade boxen version to 2.5.0

Closes #554
updated boxen-git to 2.3.0
bump version on modules (includes ruby heartbleed fix)
Fix to support LLVM/ruby that ships with Xcode 5.1
Added boxen upgrade instructions
update Puppetfile homebrew version
Added more detailed update process
Moved Upgrading instructions to FAQ
fixed spelling error
Update README.md

Other boxem fixed.