Remove add-from-bower #121

Even though I implemented this feature, I think it's proven to only confuse users into thinking they will get some kind of "extra-deps" behavior, and this really should exist as a separate tool that just uses bower-the-library (e.g. I have the beginnings of one here: https://github.com/justinwoo/get-package-def).

I've basically already implemented the core of what this is for my own package sets project anyhow with a simple Perl script: https://github.com/justinwoo/spacchetti/blob/c2a7cc4fdaadba2d09cb077fea2758e74e3f2818/prepare-bower.pl

So can we get to removing this? Is there anyone who actually likes add-from-bower and can speak for it?