Consistent after save and updateAttributes

-  Ensure consistent behavior in ActiveRecord::afterSave() (fixes #4012)
- changed updateAttributes to be more simple update (fixes #3233)
@cebe 
>to be named after the exact event.

but you named it `AFTER_SAVE` ) 

>they just carry the data

it would be even better if one will realize that events are different and some data in one event (currently `ActionEvent` , `MailEvent` not needed in other). That was all explained in #3882 .

>There is no sense in creating two exactly equal classes for this.

Nobody asks for extracting it for them , main thing is `saving`, so we can add `isUpdate` or `isInsert` into event class of `AfterSaveEvent` .

Overall it is question of logic . Because we can easily create one big `ActiveRecordEventForAll` and put it all there, so it is all about logic and good practices and understanding of applications design )