Cancel change event

[neilmonroe]

There is currently no way to cancel a change event since the value has already been set.

The desired behavior in the case of some logic in the change handler which decides that the select should, in fact, not be changed (user confirmation, etc.) would be to return the value false from this function.

The value of the dropkick element can be reverted to the original value with the "reset" method, but if the user has already made a change from the default, then this would not be appropriate.