Ogm 521 natural one to one

https://hibernate.atlassian.net/browse/OGM-521

This patch will remove the redundant column created for *ToOne associations on nodes.
I add to add some metadata in the TupleContext to achieve this.
Actually my idea was that people might be surprise to not see the property on the node. I don't think ther is need to explain it since I basically tell that at the beginning of the section