NF11 Tax Rate Tab in Tax Category

Goal: Functional

Developer: Zuhri Utama

Feature Ticket: IDEMPIERE-4648

Description

There's a new tab in the Tax Category window that allows users to work with tax rates directly from this window. This is beneficial because:

1. This makes it easier to work with tax rates because they are already appropriately filtered.
2. It might make it easier for newbies to understand the logic of the taxation setup if the tabs are organized like this.