* lisp/vc/ediff-mult.el (ediff-filegroup-action):
* lisp/vc/ediff.el (ediff-directories,ediff-directory-revisions,
ediff-directories3, ediff-merge-directories,
ediff-merge-directories-with-ancestor, ediff-merge-directory-revisions,
ediff-merge-directory-revisions-with-ancestor): Clarify prompt message for
filename filter in interactive ediff. The new message makes it clear what is
being filtered