duplicating boats and banner patterns

*Additional information (by [~Auldrick])*

As expected, the creative inventory Items category contains a group named Boats that has the 6 items for boats of each wood species. This category also has a group named Banner Patterns that has the 6 items for predefined banner patterns.

However, both groups also appear under the Nature category, with the Boats group containing only Oak Boat and the Banner Patterns group containing only Creeper Charge.