Complex.Cinv_conj and Cdiv_conj without precondition
As noticed in QuantumLib.Complex, no need for non-zero preconditions in Cinv_conj and Cdiv_conj.
The usual trade-off here : existing proofs may break after these preconditions are removed (but should be easy to fix), while future proofs will be simpler. That's up to you...
Best regards, Pierre