compose-publish.el: added color link

Added color link to org-mode. They are used with [[color:xxx][text to be colored]]. The code comes from this page : https://orgmode.org/worg/org-faq.html#org64ae339

compose-publish.el

@@ -170,6 +170,23 @@ undesirable behavior."
    (prefix-all-lines "#+HTML_HEAD_EXTRA: " body)
    "\n#+HTML_HEAD_EXTRA: \\)</div>\n"))
 
+;; To include easy color links in org-mode
+;; now simply use [[color:red][text to be in red]]
+;; https://orgmode.org/worg/org-faq.html#org64ae339
+(org-add-link-type
+ "color"
+ (lambda (path)
+   (message (concat "color "
+                    (progn (add-text-properties
+                            0 (length path)
+                            (list 'face `((t (:foreground ,path))))
+                            path) path))))
+ (lambda (path desc format)
+   (cond
+    ((eq format 'html)
+     (format "<span style=\"color:%s;\">%s</span>" path desc))
+    ((eq format 'latex)
+     (format "{\\color{%s}%s}" path desc)))))
 
 ;; fullpath from relative path
 ;; http://xahlee.info/emacs/emacs/elisp_relative_path.html