Update config.xml

Updating message to be a little more helpful

Author: ralbin

app/code/Magento/Multishipping/etc/config.xml

@@ -15,7 +15,7 @@
         </multishipping>
         <sales>
             <minimum_order>
-                <multi_address_error_message>All shippable products have been removed from your order</multi_address_error_message>
+                <multi_address_error_message>The current cart does not match multi shipping criteria, please review or contact the store administrator</multi_address_error_message>
             </minimum_order>
         </sales>
     </default>