This is a follow-up to a previous discussion on emacs-devel[1].

The attached patch makes `remove-hook` interactive.  A common use case
for remove-hook is to fix your own mistakes when programming Emacs:
renaming a hook function for something more expressive, moving a
function to a different hook or from global to local, and so on.  For
these cases, it seems more natural to use the function interactively
than to have to write throwaway lisp one-liners.

A limitation of this approach is that since completion requires a text
representation of the function to remove, if two hooks have the same
representation under `princ` it will be impossible to distinguish
between them.  In this case, which is probably *extremely* rare (and
only concerns anonymous functions), only the first one will be
removed.

The copyright assignment paperwork was completed on Dec, 11.

[1] See: https://lists.gnu.org/archive/html/emacs-devel/2020-11/msg00860.html