Recommended way to get front and back element

What is your recommendation to read `front` and `back` element out of circular buffer. The Boost circular buffer allows reading `front` and `back` (docs: https://www.boost.org/doc/libs/1_78_0/doc/html/boost/circular_buffer.html). I think it will be a good adition to the API. 

If I add `front` and `back` methods to the public API, would you be open for a PR?