Better validation of input about balanced-js

[mjallday]

1. library should not be minified - https://js.balancedpayments.com - let's make a new issue to un-minify that
2. if you pass a function should we try and evaluate the response?
3. by warning what do you mean? console.warn or something in the callback?
4. I agree that promise could be nice.

[gr0uch]

1.) It would be nice to build an unminified version, but we should also not encourage its use in production.
2.) I don't think so, that would be too magical.
3.) console.warn should be sufficient.
4.) What about using Q or RSVP.js? they're both ~2.5kb minified+gzipped.