bug#20728: 25.0.50; grep and grep-find templates should have a place holder for the --color argument

[Dmitry Gutov]

On 06/28/2015 11:28 PM, Eli Zaretskii wrote:

> See cedet/semantic/symref/grep.el for when we don't want 'always'.

We don't want `auto' there either, do we?

> > Do we even have Grep-related commands that use a pipeline that doesn't
> > end with Grep?
>
> I don't know.

So I propose to eliminate the value `auto'. It seems we only had it as a 
maybe-solution for third-party code not to have to recompute the Grep 
defaults with grep-highlight-matches set to nil.

But now we can simply bind it to nil.