Added mailcatcher incl. upstart job

[Mailcatcher](http://mailcatcher.me) is a neat little tool which allows you to intercept all outgoing mail and display it in a nice web UI. This way you don't have to setup an mail account or change smtp credentials just to test your projects mail sending capabilities.

This will install mail catcher, forward the web UI to port 10800 and install an upstart job.

Mailcatchers dummy smtp server runs on port 1025, not credentials or TLS needed.