redding/mr — pull request #17 by jcredding (2013-05-24 19:55:49+00:00)
Title: Fix writing nil belongs to associations

This fixes a bug where belongs to associations would throw an
exception when they were given a `nil` value. This was because
the associations check to make sure they are writing `MR::Model`
values. This allows writing `nil` values which correctly sets the
underlying association to `nil`.

Closes #12