New Tramp method "run0"

New Tramp method "run0"

* doc/misc/tramp.texi (Quick Start Guide, Inline methods)
(Password handling, Predefined connection information)
(Ad-hoc multi-hops): Add "run0".
(Remote processes): Mention tramp-use-connection-share.

* etc/NEWS: New Tramp method "run0".

* lisp/net/tramp.el (tramp-completion-dissect-file-name):
* lisp/net/tramp-cmds.el (tramp-list-remote-buffers):
* lisp/net/tramp-smb.el (tramp-smb-handle-insert-directory):
Use `tramp-compat-keep-seq'.

* lisp/net/tramp-cmds.el (tramp-file-name-with-method): Add "run0".

* lisp/net/tramp-sh.el (tramp-enable-run0-method): New defun.
(tramp-sh-handle-expand-file-name): Add "run0".
(tramp-maybe-open-connection): Simplify setting timeout.

(cherry picked from commit b43c31d2f50dc71680dfd62412ce9b9afb6c65a4)