org-exp: fixed small bug, use match data before it's overwritten by looking-at

  Patch by Carsten

* lisp/org-exp.el (org-export-mark-blockquote-verse-center): fixed
  small bug, now grabbing match data before overwritten by looking-at
  this fixes a problem with remainders of #+end_quote lines appearing
  in exported output

lisp/org-exp.el

@@ -1568,8 +1568,8 @@ These special cookies will later be interpreted by the backend."
       (setq beg (match-beginning 0)
 	    beg1 (1+ (match-end 0)))
       (when (re-search-forward (concat "^[ \t]*#\\+end_" type "\\>.*") nil t)
-	(setq end (+ (point-at-eol) (if (looking-at "\n$") 1 0))
-	      end1 (1- (match-beginning 0)))
+	(setq end1 (1- (match-beginning 0))
+	      end (+ (point-at-eol) (if (looking-at "\n$") 1 0)))
 	(setq content (org-remove-indentation (buffer-substring beg1 end1)))
 	(setq content (concat "ORG-" (upcase t1) "-START\n"
 			      content "\n"