Add LM implementations of CSWAP & Toffoli gates

[multiphaseCFD]

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[chaeyeunpark]

Thanks @multiphaseCFD for taking this! I expect that LM version of those gates do not really give a visible speed-up (or can be slower), but it is better to see how it works.

[multiphaseCFD]

Thanks @multiphaseCFD for taking this! I expect that LM version of those gates do not really give a visible speed-up (or can be slower), but it is better to see how it works.

Thanks @chaeyeunpark! I agree and will try to work on it later.