Improve package.json and bower.json

This PR adds the required and recommended information to `package.json` so that this module can be published to NPM. I also took the liberty to update `bower.json` with some recommended information and dependencies.

I named the package "backbone-validator.js" because both "backbone-validator" and "backbone.validator" are already taken in npm. "backbone-validator.js" however seems to be available at the moment. Feel free to change it though.

To publish the package to npm, please follow the guide here: https://gist.github.com/coolaj86/1318304. But to be honest, you can skip the pakmanager stuff - and also - we already have a package.json in place. So you really only need to create a user on npm and publish.

Also, FYI: http://stackoverflow.com/questions/13507763/do-i-need-to-publish-to-npm-every-time-i-update-a-package-available-via-git