ox: Remove #+KEYWORD and #+DESCRIPTION

* ox.el: Remove #+KEYWORD: and #+DESCRIPTION:.
* ox-deck.el, ox-rss.el, ox-html, ox-latex, ox-odt, ox-org: Add
  #+KEYWORD and #+DESCRIPTION.
* org.texi (Export settings): Explicit state which backends
  support #+DESCRIPTION and #+KEYWORDS.

contrib/lisp/ox-deck.el

@@ -51,7 +51,9 @@
 	      (if a (org-deck-export-to-html t s v b)
 		(org-open-file (org-deck-export-to-html nil s v b)))))))
   :options-alist
-  '((:html-link-home "HTML_LINK_HOME" nil nil)
+  '((:description "DESCRIPTION" nil nil newline)
+    (:keywords "KEYWORDS" nil nil space)
+    (:html-link-home "HTML_LINK_HOME" nil nil)
     (:html-link-up "HTML_LINK_UP" nil nil)
     (:deck-postamble "DECK_POSTAMBLE" nil org-deck-postamble newline)
     (:deck-preamble "DECK_PREAMBLE" nil org-deck-preamble newline)

contrib/lisp/ox-rss.el

@@ -122,7 +122,9 @@ When nil, Org will create ids using `org-icalendar-create-uid'."
 	      (if a (org-rss-export-to-rss t s v)
 		(org-open-file (org-rss-export-to-rss nil s v)))))))
   :options-alist
-  '((:with-toc nil nil nil) ;; Never include HTML's toc
+  '((:description "DESCRIPTION" nil nil newline)
+    (:keywords "KEYWORDS" nil nil space)
+    (:with-toc nil nil nil) ;; Never include HTML's toc
     (:rss-extension "RSS_EXTENSION" nil org-rss-extension)
     (:rss-image-url "RSS_IMAGE_URL" nil org-rss-image-url)
     (:rss-categories nil nil org-rss-categories))

doc/org.texi

@@ -10682,8 +10682,9 @@ exported.}.
 @item DESCRIPTION
 @cindex #+DESCRIPTION
 The document description.  Back-ends handle it as they see fit (e.g., for the
-XHTML meta tag), if at all.  You can use several such keywords for long
-descriptions.
+XHTML meta tag), if at all.  The keyword is supported by @LaTeX{} back-ends,
+HTML back-ends, ASCII back-ends, the Texinfo back-end, and the ODT back-end.  You
+can use several such keywords for long descriptions.
 
 @item EMAIL
 @cindex #+EMAIL
@@ -10693,8 +10694,10 @@ The email address (@code{user-mail-address}).
 @item KEYWORDS
 @cindex #+KEYWORDS
 The keywords defining the contents of the document.  Back-ends handle it as
-they see fit (e.g., for the XHTML meta tag), if at all.  You can use several
-such keywords if the list is long.
+they see fit (e.g., for the XHTML meta tag), if at all.  The keyword is
+supported by @LaTeX{} back-ends, HTML back-ends, ASCII back-ends, the Texinfo
+back-end, and the ODT back-end.  You can use several such keywords if the list
+is long.
 
 @item LANGUAGE
 @cindex #+LANGUAGE

lisp/ox-html.el

@@ -110,6 +110,8 @@
   :options-alist
   '((:html-doctype "HTML_DOCTYPE" nil org-html-doctype)
     (:html-container "HTML_CONTAINER" nil org-html-container-element)
+    (:description "DESCRIPTION" nil nil newline)
+    (:keywords "KEYWORDS" nil nil space)
     (:html-html5-fancy nil "html5-fancy" org-html-html5-fancy)
     (:html-link-use-abs-url nil "html-link-use-abs-url" org-html-link-use-abs-url)
     (:html-link-home "HTML_LINK_HOME" nil org-html-link-home)

lisp/ox-latex.el

@@ -108,6 +108,8 @@
     (:latex-class-options "LATEX_CLASS_OPTIONS" nil nil t)
     (:latex-header "LATEX_HEADER" nil nil newline)
     (:latex-header-extra "LATEX_HEADER_EXTRA" nil nil newline)
+    (:description "DESCRIPTION" nil nil newline)
+    (:keywords "KEYWORDS" nil nil space)
     ;; Other variables.
     (:latex-active-timestamp-format nil nil org-latex-active-timestamp-format)
     (:latex-caption-above nil nil org-latex-caption-above)

lisp/ox-odt.el

@@ -97,6 +97,8 @@
 		(org-open-file (org-odt-export-to-odt nil s v) 'system))))))
   :options-alist
   '((:odt-styles-file "ODT_STYLES_FILE" nil nil t)
+    (:description "DESCRIPTION" nil nil newline)
+    (:keywords "KEYWORDS" nil nil space)
     ;; Other variables.
     (:odt-content-template-file nil nil org-odt-content-template-file)
     (:odt-display-outline-level nil nil org-odt-display-outline-level)

lisp/ox.el

@@ -102,8 +102,6 @@
     (:date "DATE" nil nil t)
     (:author "AUTHOR" nil user-full-name t)
     (:email "EMAIL" nil user-mail-address t)
-    (:description "DESCRIPTION" nil nil newline)
-    (:keywords "KEYWORDS" nil nil space)
     (:language "LANGUAGE" nil org-export-default-language t)
     (:select-tags "SELECT_TAGS" nil org-export-select-tags split)
     (:exclude-tags "EXCLUDE_TAGS" nil org-export-exclude-tags split)