ox-ascii: Ignore line breaks when removing duplicates links

* lisp/ox-ascii.el (org-ascii--unique-links): Ignore white spaces when
  uniquifying links in section.

Thanks to Mathias Bauer for reporting it.
http://permalink.gmane.org/gmane.emacs.orgmode/84548

lisp/ox-ascii.el

@@ -750,7 +750,6 @@ generation.  INFO is a plist used as a communication channel."
 
 (defun org-ascii--unique-links (element info)
   "Return a list of unique link references in ELEMENT.
-
 ELEMENT is either a headline element or a section element.  INFO
 is a plist used as a communication channel."
   (let* (seen
@@ -760,8 +759,14 @@ is a plist used as a communication channel."
 	   ;; Update SEEN links along the way.
 	   (lambda (link)
 	     (let ((footprint
+		    ;; Normalize description in footprints.
 		    (cons (org-element-property :raw-link link)
-			  (org-element-contents link))))
+			  (let ((contents (org-element-contents link)))
+			    (and contents
+				 (replace-regexp-in-string
+				  "[ \r\t\n]+" " "
+				  (org-trim
+				   (org-element-interpret-data contents))))))))
 	       ;; Ignore LINK if it hasn't been translated already.
 	       ;; It can happen if it is located in an affiliated
 	       ;; keyword that was ignored.