Documentation for View/Entity
Model: minor fix of destroy()

destroy() was calling this.off(null), where it only needs to call
this.off() to unbind all bindings to this.
View/Entity: moving prerender event to proper time

prerender event was being fired for every call to .render(), it should
only do so before .template() is called.
docs: fixing up event name documentation

Events are now documented near the top.