update OGC services

Author: jmckenna

en/ogc/wcs_server.txt

@@ -238,8 +238,8 @@ utilizing the raw image modes::
     FORMATOPTION "FILENAME=result.grd"
   END
 
-The *FORMATOPTION FILENAME* defines the preferred name of the resulting
-file from WCS GetCoverage requests.
+The *FORMATOPTION FILENAME* defines the preferred name of the file returned 
+from WCS GetCoverage requests.
 
 .. TIP::
    The :ref:`MapServer WCS Use Cases <wcs_format>` document has more examples