Have the right anchors in documentation to help search engines

[ViralBShah]

For example, when you google "julia kron doc", it sends you to the LinearAlgebra documentation at https://docs.julialang.org/en/v1/stdlib/LinearAlgebra/. If possible, we should have the right anchors on the page so that search engines can send you directly to the relevant section on that page.

Or alternatively, it would be nice to have one page per function (although many would then look a bit empty, since they are often terse).

cc @Keno @StefanKarpinski

[mortenpi]

Hmm. We put the name of each of the docstrings in a <header> tag (inside the <article> container of each docstrings), whereas maybe we should use <h1> instead (based on looking at mdn for <article> and <header>).

[MarkNahabedian]

Would leaving a name anchor, e.g. <a name="fragment"/> help here?

[mortenpi]

Looking at the docs, the name attribute looks to be the same as id and seems to be pretty much deprecated. And we already have anchors with ids:

I still think that using a proper heading, instead of the <header> tag, should promote this for the search engines.