Re-create static site for Rust course

[brson]

I had an idea to present the entire set of course material in a single consistent site. At the moment though it is not worth doing though, mostly because all the content is well-presented through the github interface itself. It made more sense when there were lesson slides that needed to be presented nicely.

I have removed the existing work on this in https://github.com/pingcap/talent-plan/pull/150.

But I still want to pursue the idea, so I'm leaving an open issue. The previous work can always be pulled out of the history.