mixonic/ranked-model — pull request #50 by metalon (2013-08-01 14:03:51+00:00)
Title: Changing position marks record as changed. Fixes #49

Changing position via setter `image_order_position=` does not persist now.

```ruby
image = Image.create # saves record to DB
image.changed? # => false
image.save # does nothing as it should
image.image_order_position = :last
image.changed? # => false
image.save # still does nothing
```