Fixed bug 574978 shutil example out of sync with source code

Doc/lib/libshutil.tex

@@ -112,10 +112,9 @@ def copytree(src, dst, symlinks=0):
                 linkto = os.readlink(srcname)
                 os.symlink(linkto, dstname)
             elif os.path.isdir(srcname):
-                copytree(srcname, dstname)
+                copytree(srcname, dstname, symlinks)
             else:
                 copy2(srcname, dstname)
-            # XXX What about devices, sockets etc.?
         except (IOError, os.error), why:
             print "Can't copy %s to %s: %s" % (`srcname`, `dstname`, str(why))
 \end{verbatim}