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
script/nuke failed to delete receipts

Can't use a bare system call because we need globbing
Merge pull request #85 from boztek/nuke-delete-receipts

Fix script/nuke to properly delete receipts
work with EDITOR like 'mate -w'
install the version you're checking for
speed up all invocations of boxen

when running Bundler, it just so happens that --local should (but does not)
skip updating the gems in vendor/cache. explicitly skipping that update drops
most of a second off of every run of boxen.
Update README for Puppet Module sharing docs
Merge pull request #86 from indirect/bundler_bootstrap

Fix bundler version install stanza
Merge pull request #87 from indirect/my-config

work with EDITOR like 'mate -w'
Merge pull request #88 from indirect/faster_boxen

speed up all invocations of boxen
README overhaul
Update Puppetfile
Correct typo in README

s/bothers/others
Don't die if HEAD ref is not symbolic.

Examples of situations when HEAD is not symbolic:

 * You're doing interactive rebase
 * You're using git bisect
 * ... and so on.
allow bundler 1.x releases
Merge pull request #126 from indirect/bundler_update

Allow Bundler 1.x releases
It's cleaner to have another case: "not on any branch".
Merge pull request #123 from paxan/dont-die-when-head-is-detached

Don't panic if your HEAD is detached
Merge pull request #116 from pedrogimenez/patch-1

Update Puppetfile