MetaProxyField needs to be more like MetaToMany when it comes to how data is stored..
ToMany is stored like so. If you have a Shirt which has a List users; then the storage is colname=users:userFk1 val=null and colname=users:Fk2 value=null, etc. etc for each user in the list.
For a ToOne, we store it like colname=users value=Fk1. We need to change it to store like the above ToMany relationship instead.
We also need to make sure it is configurable so you can go with the old way as well as some models may already exist and someone wants to put a playorm client on top of the existing model. The default should be this new way with an annotation to revert to the old way though.