Fix embedded objects not populated on queries.

OGM-557

The new unit test shows the problem with @Embedded objects not being populated by a query (not find).
There was a lot of similar code between MassIndexingMongoDBTupleSnapshot.java and MongoDBTupleSnapshot.java that I refactored.
This method name doesn't look very Java-ish :) Something more consistent with the others in this class would be nice.