Add interactive readme command

[lodagro]

Description

Feature request: add a new function (maybe named zprezto-readme) which allows easy access to the modules README files.

Expected behavior

For example zprezto-readme git will show the git module README file. If bat is available use bat -p otherwise fall back to cat or more.

[belak]

I like this idea, but I don't think I'll have time to develop it any time in the near future.

[belak]

Alternatively, it may be possible to export these as man pages and add a directory to the $MANPATH

[srijanshetty]

@belak I like the man pages idea, let me see if I can do something about it. Do you propose we have a manpage for each module? Or just the main README?

[lodagro]

My idea was to have it for each module.

[belak]

I think I'd imagine something similar to how git works, where there's a main git man page, but also git-commit for sub-commands. Maybe we could do that for modules?