bug#33541: 26; Doc string of `align-regexp'

[Eli Zaretskii]

> Date: Thu, 29 Nov 2018 12:22:18 +1300
> From: Phil Sainty <psainty@orcon.net.nz>
> Cc: 33541@debbugs.gnu.org
> 
> I think the docstring is clear, provided that you read all of it; but
> it could undoubtedly be improved, especially as this is a slightly
> fiddly command to get to grips with.
> 
> Perhaps your concern could be addressed by tweaking the paragraph
> starting "REGEXP must contain at least one parenthesized subexpression"
> so that it says:
> 
> "Non-interactively, REGEXP must contain at least one parenthesized...."
> 
> (which strictly speaking is perhaps less correct than what it says now,
> yet I think in practice would make things slightly clearer.)
> 
> I would also change "automatically added" to "automatically prefixed".

Patches to improve that doc string are welcome.