(sgml-mode-map): Use it, defined additional long keys to compensate.
(sgml-tag-alist): Added <![ ]>
(sgml-tag): Special treatment for previous construct.
(sgml-auto-attributes): Deleted variable covered by sgml-quick-keys,
changed function of same name.
(sgml-delete-tag): Newline also counts as whitespace before tag.
(html-quick-keys): Use sgml-quick-keys as default, thus changed to nil.
(html-mode-map): Added C-c C-c char combinations for when
html-quick-keys is nil.
(html-tag-alist): Added /cgi-bin/ to href completions, submit (spelling
fixed) button to form.
(html-checkboxes): New skeleton.
(sgml-specials, sgml-name-8bit-mode, sgml-char-names)
(sgml-font-lock-keywords, sgml-face-tag-alist, sgml-tag-face-alist)
(sgml-display-text, sgml-tag-alist, sgml-tag-help)
(sgml-auto-attributes): New variables.
(sgml-mode-common): New function.
(sgml-mode): Most code moved to it.
(sgml-name-char, sgml-name-self, sgml-maybe-name-self)
(sgml-name-8bit-mode, sgml-tag, sgml-attributes, sgml-auto-attributes)
(sgml-tag-help, sgml-maybe-end-tag, sgml-skip-tag-backward)
(sgml-skip-tag-forward, sgml-tags-invisible): New commands.
(sgml-beginning-of-tag, sgml-value): New functions.
