Bin wrapper to simplify usage and make use of gntp

Please don't pull yet, still needs some testing and docs.

This adds bin/coffee-notify.js

It has a help (node bin/coffee-notify.js --help) to show the usage options.

For gntp it needs gntp-send. If you have it installed via the PPA the default path should work, otherwise you can specify where you've built it.

Any questions/suggestions? Is this something you'd be willing to pull (once docs are there)?