title: Copying from EntityCollection to EntityCollection impossible?
body: <p>How would you do this (pseudo code): product1.Orders.AddRange(product2.Orders);</p>
  
  <p>However, the function "AddRange" does not exist, so how would you copy all items in the EntityCollection "Orders" from product2 to product1?</p>
  
  <p>Should be simple, but it is not...</p>