Minor wording change in section title.

Doc/lib/libfileinput.tex

 \section{\module{fileinput} ---
-         Iteration over lines from multiple input streams.}
+         Iterate over lines from multiple input streams}
 \declaremodule{standard}{fileinput}
 \moduleauthor{Guido van Rossum}{guido@python.org}
 \sectionauthor{Fred L. Drake, Jr.}{fdrake@acm.org}