Autoload tramp-archive

Autoload tramp-archive

* doc/misc/tramp.texi (Archive file names): Do not require to
load Tramp explicitly, this is autoloaded now also for file archives.

* lisp/net/tramp-archive.el (tramp-archive-suffixes)
(tramp-archive-compression-suffixes): Autoload them.
(tramp-archive-autoload-file-name-regexp): New defmacro.
(tramp-archive-file-name-regexp): Use it.
(tramp-register-archive-file-name-handler): New defun.  Call
it in `after-init-hook'.

* test/lisp/net/tramp-archive-tests.el
(tramp-archive-test40-file-system-info): Rename from
`tramp-archive-test40-archive-file-system-info.
(tramp-archive-test42-auto-load)
(tramp-archive-test42-delay-load): New tests.