3.0 behavior registry updates

A continuation of #3492 and #3494.

Changed the `Table::behaviors()` method to match the `Table::associations()`  (and `Controller:components()`) method. It now returns the BehaviorRegistry instance for the table. I left in the `removeBehavior()` method to complement `addBehavior()`, but this can be removed if required.

The BehaviorRegistry was updated to take into account loaded behaviors when calling methods and finders, or when loading a behavior.