Reload screen after creating purchase from purchase request

This way the user see that the selected purchase requests have been purchased
as they are no longer in the draft tab.

modules/purchase_request/purchase_request.py

@@ -556,6 +556,9 @@ class CreatePurchase(Wizard):
             compute_qty(r.uom, r.quantity, unit, round=False)
             for r in requests)
 
+    def end(self):
+        return 'reload'
+
 
 class HandlePurchaseCancellationException(Wizard):
     'Handle Purchase Cancellation Exception'