Complete first draft of "distributed compute" section

[jeromekelleher]

In #87 I added a first pass at some paragraphing and citations for the "Distributed compute" section, which I'm hoping is so bad that it will infuriate @hammer or @tomwhite into coming along and fixing it.

Any takers for tidying up this section into a non-terrible state It can be either here or Overleaf, I don't mind, but it would be good to assign someone so we don't have parallel updates.