Remove Bower dependency

[ascott1]

This moves us to completely using npm to manage packages on the front-end.

To test:

1. Clone my branch locally and run the frontendbuild.sh script. This will run npm install and the grunt build command. The site should build with no errors.
2. Start the server and ensure that there are no console.log errors reporting unfound scripts.

   Review

@willbarton

[willbarton]

[willbarton]

Did you mean to commit regulations/static/regulations/js/built/lib/respond/respond.min.js?

[cmc333333]

Ugh. We should have sent this up: https://github.com/18F/regulations-site/pull/62

Highlights relevant for you:

• README changes
• unveil for images needed to be replaced as it was being pulled in from bower

[ascott1]

Ugh. We should have sent this up: 18F#62

Double ugh.

• README changes coming.
• I had long ago replaced Unveil with my own version with the same API, which allowed us to write unit tests for the JS views.

Did you mean to commit regulations/static/regulations/js/built/lib/respond/respond.min.js?

@willbarton nope. fix coming.

[ascott1]

This should be all set, unless @cmc333333 would rather PR the 18F changes (which I'm also ok with)

[willbarton]