dtmtec/backbone-nested-attributes — pull request #13 by igwan (2014-10-17 15:30:52+00:00)
Title: allow to change the _destroy attribute by setting destroy_action.

I needed a way to nullify a relation instead of destroying the child so I added a way to specify a custom destroy attribute like so :
```coffeescript
relations: [
type: 'many'
key: 'thumbnails'
relatedModel: -> Entities.Thumbnail
destroy_action: '_remove'
]
```

So now I can just add to my Rails child model :
```ruby
def _remove
!gallery_id.nil?
end

def _remove=(bool)
update_attribute :gallery_id, nil if bool
end
```