change $USER to ${USER} to avoid history expansion

see [here](http://stackoverflow.com/questions/15140221/weired-zsh-behavior-how-to-debug/)
Merge pull request #83 from rweng/patch-1

change $USER to ${USER} to avoid history expansion
added stuff
finally got it working by clearing out my Puppetfile and jcowhigjr.pp
Merge branch 'master' of https://github.com/boxen/our-boxen

* 'master' of https://github.com/boxen/our-boxen:
  change $USER to ${USER} to avoid history expansion
removed jcowhigjr.pp
ran script/boxen --profile --debug