Fix for displaying entities ending in a number

* lisp/org.el (org-fontify-entities): Fix bug: The entities \sup[123] and
  \there4 were not "prettified" when org-pretty-entities was enabled.

TINYCHANGE

lisp/org.el

@@ -5966,7 +5966,7 @@ needs to be inserted at a specific position in the font-lock sequence.")
     (when org-pretty-entities
       (catch 'match
 	(while (re-search-forward
-		"\\\\\\(frac[13][24]\\|[a-zA-Z]+\\)\\($\\|{}\\|[^[:alpha:]\n]\\)"
+		"\\\\\\(there4\\|sup[123]\\|frac[13][24]\\|[a-zA-Z]+\\)\\($\\|{}\\|[^[:alpha:]\n]\\)"
 		limit t)
 	  (if (and (not (org-in-indented-comment-line))
 		   (setq ee (org-entity-get (match-string 1)))