Shopify/identity_cache — pull request #108 by arthurnn (2013-12-05 05:54:25+00:00)
Title: Add column_types init for AR 4

see:
https://github.com/rails/rails/blob/master/activerecord/lib/active_record/core.rb#L172

AR 4.0 init a `@column_types` to be used when reading an attribute. When not calling `init_with` we need to pre-setup that.

review @camilo @dylanahsmith @jduff