Affects Version/s: None
Fix Version/s: 12_01_17
Steps to reproduce:
1. Create a model with a few fields
2. Persist a few of these models
3. Add a new field called "new_field"
4. Try ModelName.first.new_field.
Rather than returning nil for new_field on models created before new_field existed, it throws a method_missing exception. It should just return nil instead.