Add support for owned entity type

[grinay]

The library creates access to an entity with "Set" method, but in scenario when we use owned entity it tries to create Dbset with the owned entity which is not allowed. It will fail with "Cannot create a DbSet for 'MyOwnedEntity' because it is configured as an owned entity type and must be accessed through its owning entity type" Hence library should find the owner and access to this property through it.