bug#22043: 25.0.50; search-forward and char folding

[Eli Zaretskii]

> From: Mike Kupfer <m.kupfer@acm.org>
> cc: Eli Zaretskii <eliz@gnu.org>, 22043@debbugs.gnu.org
> Date: Sun, 29 Nov 2015 20:53:02 -0800
> 
> > Perhaps, to be more precise, the difference is search that
> > does or does not accept general regexp patterns as _input_.
> > Those that do have "regexp" (or "-re-"?) in their name;
> > those that do not do not have it.  The former do not
> > support char folding; the latter do.  Is that correct (and
> > complete)?
> 
> I'm afraid it's more complicated than that.  If nothing else, there's
> the "word" family of search functions, which don't do character folding.

Yes, exactly.  And also symbol search, etc.

I've just realized that the effect of the toggles on the search mode
is not documented in the doc strings of the toggles or in the manual,
so I added that.