`character-fold-search' should be a user option, like `case-fold-search'

[Drew Adams <drew.adams@oracle.com>]

Subject line says it all.  Users should be able to customize
this variable, to decide for themselves, without fiddling with
`setq', whether search starts by default with or without
character folding.  They should be able to find this easily,
as an option in custom group `matching', right alongside
`case-fold-search'.

No?

I customized `case-fold-search' to nil long ago, and I will
likely do the same for `char-fold-search': set it to nil.
By default I want search to distinguish different characters.

Different users have different uses and different preferences.

Fortunately, the behavior can be toggled.  But the default
behavior should also be customizable.  Users should not need
to use `setq' for `char-fold-search' but be able to customize
`case-fold-search'.  This is a (minor) step backward, IMO.