Support GitHub Markdown in Docker Hub Readme text

[BretFisher]

Tell us about your request I'd like my emoji's and other GitHub Markdown features to work the same in Docker Hub.

Which service(s) is this request for? Docker Hub

Tell us about the problem you're trying to solve. What are you trying to do, and why is it hard? Example: :wave: doesn't work in Docker Hub readme's.

[nebuk89]

Emojis as the top one or would something like anchors be more interesting to start 👀