Remove some timestamp format assumptions
Don’t assume that current-time and plain encode-time return timestamps in (HI LO US PS) format. * lisp/gnus/gnus-art.el (article-make-date-line) (article-lapsed-string): * lisp/gnus/gnus-demon.el (gnus-demon-time-to-step): * lisp/gnus/gnus-diary.el (gnus-user-format-function-d): * lisp/gnus/nnmaildir.el (nnmaildir-request-expire-articles): * lisp/net/pop3.el (pop3-uidl-dele): * lisp/org/ox-publish.el (org-publish-sitemap): * lisp/vc/vc-hg.el (vc-hg-state-fast): Simplify and remove assumptions about timestamp format. * lisp/gnus/gnus-art.el (article-lapsed-string): * lisp/gnus/gnus-diary.el (gnus-user-format-function-d): Do not worry about time-subtract returning nil; that's not possible. * lisp/gnus/gnus-diary.el (gnus-user-format-function-d): Avoid race due to duplicate current-time calls. * lisp/vc/vc-hg.el (vc-hg--time-to-integer): Remove; no longer used.