Allow behaviors to be baked

If you bake a tree model (actsAs Tree) and you got lft/rgt/parent fields bake should be able to auto-detect this.

Derived from tryouts back in 2011 - see https://cakephp.lighthouseapp.com/projects/42648/tickets/1781-plugin-information-gets-lost-during-baking

Can be further enhanced to also support plugin behaviors (Sluggable for slugged field, ) etc.