Copy duplicating curves

[rusu24edward]

copy work because it adds curves as it goes through the loop of curves. For example, A B and E exist. When copy goes through the loop, it copies A creating C, copies B creating D, then it copies C, which was just created, creating F, etc.

It should generate curves C and D from A and B and curve F from E.

Originally posted by @rusu24edward in #212 (comment)