Fix for git credentials containing an '=' sign

Thanks @dbussink
Merge pull request #628 from boxen/args-may-contain-equals

Fix for git credentials containing an '=' sign
updated to latest dependencies
update ruby stuff
Merge pull request #633 from boxen/update-deps

Update Puppet and Ruby dependencies
Merge branch 'refs/heads/our-boxen/master'
Updated Puppet modules and Ruby gems.
Fixed filename for the default Mandrill manifest.
Updated the README.

Include new packages and installation instructions for Mandrill.
White space cleanup.