store no longer overrides RESTAdapter#updateRecord

As soon as the
[wrap_update_response](https://github.com/rathrio/susuba/pull/1) is
accepted, this can be merged into master to remove the no longer used
overriding of the updateRecord method in the RESTAdapter
Merge pull request #3 from jugglinghobo/remove_update_override

store no longer overrides RESTAdapter#updateRecord