Add the ability to include timestamps in a data model
When I add a record with Timestamps, it has created and updated times
Move specs for Timestamps to own spec file
When creating a data model from a model with Timestamps, add the updated and created time
Refactor some specs and the implementation of updating a data model
Update time stamps when updating a model
Update updated_at timestamp when updating a single field
Update updated_at field when incrementing a single field
Update updated_at timestamp when removing a value from an array field
Update updated_at timestamp when adding a value to an array field