Non-unique names are not supported in the dataModel

[chrisala]

It's possible right now to use duplicate names in the data model in different nested contexts, however when the code matches a viewModel to the corresponding data model it does a full search by name and will always find the first occurrence of that name.
This will lead to incorrect application of validation rules, constraints and behaviours.

We should either validate and disallow duplicates, or use the current context to be able to correctly identify which data model element is meant when referencing the dataModel from the view model.