Jchansen/add cdn references

This pull request is focused on page load time.  I moved a lot of the original JavaScript CDN dependencies into local installations (with Bower) and then had the gulp build process bundle and minify all the files.  The downside of this was that it made one massive file (~1.4MB), which was ~500kb minified.  But having one large file turned out to be noticeably slower than a using a CDN for 10+ dependencies.  So I changed all dependencies to use the minified CDN versions (except for Backbone.BabySitter which doesn't have a CDN host).  RequireJS also supports a array fallback syntax, where you can use a local version as a fallback for the CDN, but I don't see a reason to use that right now.  I may end up removing the Bower packages...still deciding.

Regarding Backbone.BabySitter, it's there because Marionette includes the AppRouter, but that's the only part of Marionette we're using.  I'll end up either removing our use of AppRouter and just using regular Backbone router, or pulling AppRouter out of Marionette and dropping the dependency on the larger file.  That's a future pull request.

1. Switched nearly all JavaScript dependencies back to using CDNs.
2. Changed the 'gulp prod' step to minify the compiled JavaScript.  This takes ~30-60 seconds depending on your machines power.
3. Remove duplicate bootstrap.css import in the public version of the site (index.html)