Add missing default value for consumable

issue2755
review477002
(transplanted from 73af8be8415d414644f3656b3bf44dc3956b3222)

product.py

@@ -77,6 +77,9 @@ class Template(ModelSQL, ModelView):
     def default_type(self):
         return 'goods'
 
+    def default_consumable(self):
+        return False
+
     def default_cost_price_method(self):
         return 'fixed'