Dired: Handle posix wildcards in directory part

Dired: Handle posix wildcards in directory part

Allow Dired to handle calls like
\(dired \"~/foo/*/*.el\"), that is, with wildcards within
the directory part of the file argument (Bug#27631).
* lisp/files.el (insert-directory-wildcard-in-dir-p): New predicate.
(insert-directory-clean): New defun extracted from insert-directory.
(insert-directory)
* lisp/dired.el (dired-internal-noselect)
(dired-insert-directory): Use the new predicate; when it's true,
handle the directory wildcards with a shell call.
* lisp/eshell/em-ls.el (eshell-ls-use-in-dired): Add/remove both advices.
(eshell-ls-unload-hook): New defun.  Use it in
eshell-ls-unload-hook instead of an anonymous function.
(eshell-ls--dired)
* lisp/ls-lisp.el (ls-lisp--dired):
Advice dired to handle wildcards in the directory part with both
eshell-ls and ls-lisp.
* etc/NEWS: Announce it.
* doc/emacs/dired.texi (Dired Enter): Update manual.
* test/lisp/dired-tests.el (dired-test-bug27631): Add test.