[bitcoin/bitcoin] Update createmultisig RPC to support segwit (#13072)

@luke-jr The existing “legacy” address type (argument to `-addresstype` command line option) causes P2SH-multisig addresses for the multisig RPC. “p2sh-segwit” will cause P2SH-P2WSH-multisig addresses, and “bech32” will cause P2WSH-multisig.

This post was last modified on June 13, 2018, 9:11 pm