Changing once a contact trigger two `change`events

[misstick]

1. I click on 1 contact,
2. I click on a tag,
3. the tag is added in the card,
4. updateTags is called once,
5. model ‘contact’ is changed once,
6. contact.changeevent is recieved twice.

I seems to come from this : @listenToOnce @, 'sync', -> @contactListener.watch @ client/app/collections/contacts.coffee l51

[m4dz]

The recent refactor of models events lifecycles should have fixed this one.