serve index.html with bundle install; bundle exec rackup

The first thing I wanted to do with the boilerplate was inspect it in my browser.  For various reasons (chromebook, security extensions in my browser), I couldn't just open it with a file url.

I took the most basic rackup configuration you could do to serve just the index page.  Since I found it useful, I thought I'd offer it up.  I won't be offended if you don't find it useful.

All it requires to work is a working ruby install and running two commands:

```
bundle install
bundle exec rackup
```

Thanks for boilerplate and cheers.