2.3 Release notes update

Merge the edireader and edi_order_template release notes into the 2.3
release notes files.  Added a blurb to the Upgrade Notes regarding the
lack of an automatic EDI template upgrade.

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