Change constants sent to CBS for cash register/sales rep

This PR changes the constant for Sales Rep to be 'DOIT ONLINE CATALOG' and adds a constant for Cash Register.

Please review: @ahoffmann @weizhong-wang @lloyd-carter @KJOYNER

src/main/edu/wisc/services/cbs/common/MagentoOrder.php

@@ -34,7 +34,10 @@ abstract class MagentoOrder
     const CREDIT_CARD_IDENTIFIER_TYPE = 'CREDIT CARD';
 
     /** @var string 'Sales Rep' who sold this order (online, so Magento) */
-    const SALES_REP = 'Magento';
+    const SALES_REP = 'DOIT ONLINE CATALOG';
+
+    /** @var string 'Cash Register' */
+    const CASH_REGISTER = 'DOIT CATALOG';
 
     /** @var string CBS value for UPS shipping method */
     const UPS_SHIPPING = 'DAYTON DELIVERY';