Implement Diceware Passphrase Generator

Note: This is a first swing. I do not have the hardware necessary to test it properly at the moment.

Fixes #163 
https://github.com/sarciszewski/OpenWireless/blob/e28f2decc8601b4ff3d5bd930d1194393875f805/app/js/diceware.js#L60 Something like this? :)