Run "TZ=UTC0 admin/update-copyright".

* lisp/apropos.el:
* lisp/mail/feedmail.el:
* lisp/mail/mail-hist.el:
* lisp/org/org-ctags.el:
* lisp/org/org-protocol.el:
* lisp/progmodes/ebnf2ps.el:
* lisp/progmodes/mixal-mode.el:
* lisp/progmodes/perl-mode.el:
* lisp/savehist.el:
* lisp/textmodes/table.el:
* lisp/vc/smerge-mode.el: Remove redundant installation instructions
for packages bundled with Emacs.

* lisp/desktop.el (desktop-lazy-idle-delay):
* lisp/files.el (dired-kept-versions)
(kept-old-versions, kept-new-versions):
* lisp/filesets.el (filesets-max-submenu-length)
(filesets-max-entry-length, filesets-tree-max-level)
(filesets-query-user-limit):
* lisp/hi-lock.el (hi-lock-file-patterns-range)
(hi-lock-highlight-range):
* lisp/ido.el (ido-max-work-directory-list):
* lisp/image/gravatar.el (gravatar-cache-ttl):
* lisp/imenu.el (imenu-auto-rescan-maxout, imenu-max-items):
* lisp/informat.el (Info-split-threshold):
* lisp/mail/hashcash.el (hashcash-default-payment)
(hashcash-default-accept-payment):
* lisp/mail/mail-hist.el (mail-hist-history-size):
* lisp/mail/smtpmail.el (smtpmail-retries):
* lisp/msb.el (msb-display-most-recently-used):
* lisp/nxml/rng-valid.el (rng-state-cache-distance)
(rng-validate-chunk-size):
* lisp/progmodes/gdb-mi.el (gdb-max-source-window-count):
* lisp/recentf.el (recentf-arrange-by-rules-min-items):
* lisp/simple.el (kill-ring-max, mark-ring-max)
(global-mark-ring-max):
* lisp/tab-line.el (tab-line-tab-name-truncated-max):
* lisp/term.el (term-buffer-maximum-size, term-input-chunk-size):
* lisp/thumbs.el (thumbs-max-image-number)
(thumbs-thumbsdir-max-size, thumbs-relief, thumbs-margin)
(thumbs-image-resizing-step):
* lisp/type-break.el (type-break-interval)
(type-break-good-rest-interval, type-break-query-interval)
(type-break-warning-repeat):
* lisp/vc/compare-w.el (compare-windows-sync-string-size):
* lisp/woman.el (woman-fill-column): Use defcustom :type natnum.

* lisp/emacs-lisp/backtrace.el (backtrace-line-length):
* lisp/doc-view.el (doc-view-conversion-refresh-interval):
Use defcustom :type natnum and allow the nil value.

* lisp/gnus/spam-stat.el (spam-stat-process-directory-age):
Use defcustom :type integer.

Remove some redundant `:group` args as well.

* lisp/mail/supercite.el: Use lexical-binding.
(completer-disable): Declare var.
(sc-set-variable): Don't rely on dynbind to access `help` variable.

* lisp/mail/mail-extr.el: Use lexical-binding.
(mail-extract-address-components): Avoid use of dynamic scoping to
refer to local vars.

* lisp/mail/mailabbrev.el: Use lexical-binding.
(mail-abbrev-make-syntax-table): Rename `_` variable to `syntax-_`.

* lisp/mail/mailheader.el: Use lexical-binding.
(headers): Don't declare as dynbound globally.
(mail-header-set, mail-header-merge): Declare `headers` as dynbound
locally, instead.  Mark those functions as obsolete.
(mail-header-format): Use `alist-get` instead of `mail-header`.

* lisp/mail/binhex.el (binhex-decode-region-external): Remove always-nil
var `firstline`.

* lisp/mail/emacsbug.el: Use lexical-binding.
(report-emacs-bug): Remove always-nil var `message-end-point`.

* lisp/mail/rmail-spam-filter.el: Use lexical-binding.
(bbdb/mail_auto_create_p): Declare variable.

* lisp/mail/rmail.el (rmail-get-new-mail): Remove always-nil var
`delete-files`.

* lisp/mail/rmailout.el: Use lexical-binding.
(rmail-output-read-file-name): Remove unused var `err`.
(rmail-convert-to-babyl-format): Remove unused var `count`.
(rmail-output-as-mbox): Remove unused vars `from` and `date`.

* lisp/mail/rmailsort.el: Use lexical-binding.
(rmail-sort-messages): Remove unused var `msginfo`.

* lisp/mail/rfc822.el: Use lexical-binding.
* lisp/mail/rmailedit.el: Use lexical-binding.
* lisp/mail/mailclient.el: Use lexical-binding.
* lisp/mail/blessmail.el: Use lexical-binding.
* lisp/mail/mail-hist.el: Use lexical-binding.
* lisp/mail/rmailkwd.el: Use lexical-binding.
* lisp/mail/rmailmsc.el: Use lexical-binding.
* lisp/mail/uce.el: Use lexical-binding.
* lisp/mail/unrmail.el: Use lexical-binding.

Run "TZ=UTC0 admin/update-copyright".

Run "TZ=UTC0 admin/update-copyright $(git ls-files)".