Set langauge value for patron info response

Ensure the 3-char language field has a value (defaulting to '000') in
the patron info response.  Without the value, there is a 3-char offset
in the response message fixed fields.

Signed-off-by: Bill Erickson <berick@esilibrary.com>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>