Show manual pages about the relevant query

[fonsp]

For example, when searching for function or hcat, the docstrings are quite technical, and we should really get people to read the manual page about the more general subject.

For example: here is the docstring for function, compared to the manual entry for function.

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I have some doubts about this feature, I'll go into that later, but thought I would just write it down. Maybe you have a similar idea that would work better?

[fonsp]

How we can (automatically) link manual pages to docstrings?

[fonsp]

A manual entry is generally very large, which creates some new challenges:

• How do we (find and) highlight the relevant parts?
• Pluto's docs window is a bit too small to do serious reading