Modified resolve_gates to return object instead of list
Modified docstring of resolve_gates method
Fixed unit test for SWAP to CNOT
Fixed unit test for ISWAP to CNOT
Fixed unit test for CSIGN to CNOT
Fixed unit test for CNOT to CSIGN
Fixed unit test for CNOT to SQRTSWAP
Fixed unit test for CNOT to SQRTISWAP
Fixed unit test for CNOT to ISWAP