Complete implementation of `file-user-id'

Complete implementation of `file-user-id'

* lisp/net/ange-ftp.el (ange-ftp-file-user-uid): New defun.  Mark
it as file name handler for `file-user-uid'.

* lisp/net/tramp-archive.el (tramp-archive-handle-file-user-uid):
Move up.  Protect `file-user-id' call for older Emacs versions.

* lisp/net/tramp-crypt.el (tramp-crypt-file-name-handler-alist):
Remove 'file-user-uid'.

* test/lisp/net/tramp-archive-tests.el
(tramp-archive-test44-file-user-uid): New test.
(tramp-archive-test48-auto-load)
(tramp-archive-test48-delay-load): Rename.

* test/lisp/net/tramp-tests.el (tramp-test44-file-user-uid): New test.
(tramp--test-asynchronous-requests-timeout): Adapt docstring.
(tramp-test45-asynchronous-requests)
(tramp-test46-dired-compress-file)
(tramp-test46-dired-compress-dir, tramp-test47-read-password)
(tramp-test48-auto-load, tramp-test48-delay-load)
(tramp-test48-recursive-load, tramp-test48-remote-load-path)
(tramp-test49-unload): Rename.