Keybase.io terminal application cheatsheet.

Cheatsheet for [Keybase.io](https://keybase.io) terminal application.

This application is still an `Alpha` and was marked as so in the cheatsheet.
Added a `Last Updated` date as well for reference.

*Edit: I added `FontAwesome` support to the cheatsheet to make it more "dynamic". Feel free to let me know if I should strip that off and leave it as text only.*