GitLab

This provides an alternative to 'ido-max-directory-size', for
directories that are statically known to be too big for Ido
completion.

* lisp/ido.el (ido-big-directories): New user option.
(ido-directory-too-big-p): Use it.

* test/lisp/ido-tests.el (ido-directory-too-big-p): New unit test.