Warn users with browsers older than IE9.

- Add warning div to layout if browser version is less than IE9.
Simplify stack with Node.js static site generator.

Instead of using middleman (a Ruby static site
generator), this is moving the entire stack to be
javascript and Node.js based.

Note: This is a squashed commit from a feature branch
      called nodejs-static-site.

- Update server to use harp config for development.
- Update readme with new oss and usage instructions.
- Use Jake as build tool (similar to rake).
- Include harp/jake dependencies for project.
- Use LESS instead of SCSS.
- Update from slim templating to jade templating.
- Move and rename view files to fit Harp structure.
- Move package.json to top level and edit contents.
- Rename the source directory to client.
- Remove all Ruby related items.