Allow setting creator flag in OPTIONS line.

doc/org.texi

@@ -7125,6 +7125,7 @@ TeX:       @r{turn on/off simple @TeX{} macros in plain text}
 LaTeX:     @r{turn on/off La@TeX{} fragments}
 skip:      @r{turn on/off skipping the text before the first heading}
 author:    @r{turn on/off inclusion of author name/email into exported file}
+creator:   @r{turn on/off inclusion of creator info into exported file}
 timestamp: @r{turn on/off inclusion creation time into exported file}
 d:         @r{turn on/off inclusion of drawers}
 @end example

lisp/org-exp.el

@@ -883,6 +883,7 @@ modified) list.")
 		  ("LaTeX" . :LaTeX-fragments)
 		  ("skip"  . :skip-before-1st-heading)
 		  ("author" . :author-info)
+		  ("creator" . :creator-info)
 		  ("timestamp" . :time-stamp-file)))
 	    o)
 	(while (setq o (pop op))