ox-bibtex: Fix bibliography location in HTML

* contrib/lisp/ox-bibtex.el (org-bibtex-process-bib-files): Fix
  insertion location of bibliography in HTML export.

Reported-by: gongzhitaao <zhitaao.gong@gmail.com>
<http://permalink.gmane.org/gmane.emacs.orgmode/104117>

contrib/lisp/ox-bibtex.el

@@ -248,6 +248,7 @@ Return new parse tree."
 		(insert (format "<div id=\"bibliography\">\n<h2>%s</h2>\n"
 				(org-export-translate "References" :html info)))
 		(insert-file-contents (concat out-file ".html"))
+		(goto-char (point-max))
 		(insert "\n</div>"))
 	       ((org-export-derived-backend-p backend 'ascii)
 		;; convert HTML references to text w/pandoc