Add Mail-in-a-Box

_[Mail-in-a-Box](https://github.com/JoshData/mailinabox) helps individuals take back control of their email by defining a one-click, easy-to-deploy SMTP+everything else server: a mail server in a box. It provides a single shell script that turns a fresh Ubuntu 14.04 LTS 64-bit machine into a working mail server, including an SMTP server, IMAP server, webmail interface, spam filtering, DKIM signing, DNS server, firewall and intrusion prevention._