Add ir.message and use custom exceptions

issue3672

message.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0"?>
+<!-- This file is part of Tryton.  The COPYRIGHT file at the top level of
+this repository contains the full copyright notices and license terms. -->
+<tryton>
+    <data group="1">
+        <record model="ir.message" id="msg_change_product">
+            <field name="text">You cannot change the product of a stock lot which has stock moves.</field>
+        </record>
+        <record model="ir.message" id="msg_lot_required">
+            <field name="text">To move product "%(product)s" you must provide a stock lot.</field>
+        </record>
+        <record model="ir.message" id="msg_only_lot">
+            <field name="text">You must select a stock lot instead of a product for "%(product)s".</field>
+        </record>
+    </data>
+</tryton>