Delete Resource Refactoring framework needs work

Currently when you delete a View model, only the view model is deleted as long as it isn't used/referenced in another view model.

If a user selects a source model, any view models that depend on the source model will also be selected for deletion.

This seems overkill.

The old Delete model framework, deleted only the selected resource and it walked through any dependent models and cleaned up any references to the model being deleted.

So suggesting that we restore the single-resource delete (for models especially) and restore the model clean-up to insure that references are removed (i.e. transformation mappings) as well as the model import.