SEO improvements

[solnic]

the two main things:

• [ ] generate a sitemap.xml of all the pages we want indexed and submit to https://search.google.com/search-console/about
  • [ ] use sitemaps' priority to make latest versions prioritized in search results

[waiting-for-dev]

instruct crawlers not to crawl individual versions, and only have then crawl latest documentation.

Are we sure it is a good idea? What about if someone is using an old version and wants to search something with version number in the query? Isn't sitemaps' priority better suited for that?

[solnic]

@waiting-for-dev good point, I updated the description to reflect that