Remove lingering db_model_proxy from sample app
Make text columns case-insensitive. No override for now
Fix relation handling, which work differently under SQL
Bugfix: defaults were being applied to aggressively
Fix Validatable#save ordering an option handling.

* valid? should not be called at all if validate == false
* If other options are passed in, still need to default validate to true
Model#save returns true to indicate success. Validatable returns when !valid?