Make implement PaneModelObserver

OPEN - task 86: Create Business(Sales-Purchases) Module 
http://github.com/DevOpsDistilled/OpERP/issues/issue/86
Impl bare Controller & Model

OPEN - task 86: Create Business(Sales-Purchases) Module 
http://github.com/DevOpsDistilled/OpERP/issues/issue/86
Set title for dialogs

OPEN - task 86: Create Business
(Sales-Purchases) Module 
http://github.com/DevOpsDistilled/OpERP/issues/issue/86
Revert "Set title for dialogs"

This reverts commit 19edd23d3cea5d59bfca9ef75f1832f5439b547a.
Make implement PaneModel

OPEN - task 86: Create Business(Sales-Purchases) Module 
http://github.com/DevOpsDistilled/OpERP/issues/issue/86
Bean SalePane Model & Controller

OPEN - task 86: Create Business(Sales-Purchases) Module 
http://github.com/DevOpsDistilled/OpERP/issues/issue/86