We need to be able to define models with complex/nested fields

```
var Book = kendo.Data.Model.define({
    id: 'id',
    field: {
        id: { type: 'string'},
        title: { type: 'string'},
        author: {
            firstName: { type: 'string'},
            lastName: { type: 'string'},        
        }
    }
});

We would also benefit of fields of type kendo.data.Model and [kendo.data.Model] (arrays of items derived from kendo.data.Model) like mongoose Documents, SubDocuments and Arrays of SubDocuments. 

DataSources are simply arrays of such models and do not need to be flat tables.

Grids should not be an issue: they could ignore all complex fields and arrays and rely on calculated fields at the root to flatten the Model.