WAI-ARIA Roles (e.g. banner, navigation, main, contentinfo)

Would you consider adding WAI-ARIA roles?

https://en.wikipedia.org/wiki/WAI-ARIA

http://www.w3.org/TR/wai-aria/roles

For example: https://github.com/westurner/initializr-bootstrap/commit/144e43e70f918f417c6748bb348ed32be258f567