Add vCard validator package

Had to add a `pip2` provider
<http://ask.puppetlabs.com/question/14473/how-to-install-python-packages-with-pip2/>
and work around overly strict umask
<https://unix.stackexchange.com/questions/166948/why-is-my-pip-installed-python-script-not-executable-for-everyone/166955#166955>/<https://github.com/terrywang/vagrantboxes/issues/16>.