Add URL crediting source of git-pr
Add diceware from @pengwynn's dotfiles

Source: https://github.com/pengwynn/dotfiles/blob/86c625d/bin/dicepass
Generate stronger and easier-to-remember passwords

  - Generate passwords using just dicewords, all lowercase, with no
    special characters. (Scandalous!) [1]
  - Use dashes between the words

[1]: http://blog.agilebits.com/2011/08/10/better-master-passwords-the-geek-edition/
Teach dicepass to accept arg for number of dicewords