Define form fields list for Vendor views

maybe was needed anyway, but esp. with "synonym" usage in underlying model,
since both the "real" and "synonym" fields were showing up

tailbone_corepos/views/corepos/vendors.py

@@ -53,6 +53,18 @@ class VendorView(CoreOfficeMasterView):
         'contact',
     ]
 
+    form_fields = [
+        'id',
+        'name',
+        'abbreviation',
+        'discount_rate',
+        'phone',
+        'fax',
+        'email',
+        'website',
+        'notes',
+    ]
+
     def configure_grid(self, g):
         super(VendorView, self).configure_grid(g)