Document type > Schemas configuration should be all merged on Schema tab.

On document type feature, the schema section of the first tab should be moved on top of the schema tab, to make the experience more consistent: user configures schemas in the schema tab, either by using existing ones or declaring a new one.

The Schema tab would be separated in 3 sections:

• Inherited schemas: depending of the type you've extended
• Add existing shemas
• Declare new schemas