Manage Default View for Model

[AaronPlave]

Implements default view management in the Model Form. Closes #1027.

Testing:

1. Create a plan and verify that the default view for the plan is the auto generated view
2. Go to the models page and edit a model
3. Select a view from the default view field on the left
4. Save the model
5. Go to the plan you created and ensure that the view you selected as default is loaded
6. Create a new plan using that same model and navigate to the plan
7. Ensure that the view you selected as default is loaded

[duranb]

Other than one small comment, it looks good!