bug#20322: 25.0.50; indent-tabs-mode should default to nil

[Stefan Monnier]

> How, then, will the users change that value? With `add-hook',
> `xxx-mode-hook' and a lambda function?

Yup.  Adding more mode-specific variables to circumvent the problem is
not a good idea.  If add-hook+lambda is considered too cumbersome, we
can wrap it in some function/macro to make it look prettier.

I personally find that Custom should grow a way to set the value of
those variables "per mode" or maybe even "per directory".


        Stefan