Add support for Sitemaps in published Hubs

[lottamus]

Sitemaps are super easy to generate from static sites since we calculate all of the routes.

[tatiana-perry]

Is there a timeframe for this?

[tbarn]

Hey @tatiana-perry - it hasn't gotten put into a sprint (yet) but we now have it in Jira internally so it is in a better place to get implemented. I'll check to see if we have near-term plans to add it in.

We are working on cleaning up the issues in this repo so nothing slips through the cracks!