Support bulk create, update and delete

[erin-noe-payne]

• AbstractClass.create() should support an array of objects. In the case of an array the result should be a single query or database transaction that acts as a bulk insert.
• AbstractClass.destroyAll() should support an optional params argument, mirroring the syntax of AbstractClass.all(). Allows us to write a bulk delete query ("DELETE FROM table WHERE ...") rather than retrieving, iterating over and deleting X number of objects.