1df206f Disallow using addresses in createmultisig (Andrew Chow)
Pull request description:
This PR should be the last part of #7965.
This PR makes createmultisig only accept public keys and marks the old functionality of accepting addresses as deprecated.
It also splits `_createmultisig_redeemscript` into two functions, `_createmultisig_getpubkeys` and `_createmultisig_getaddr_pubkeys`. `_createmultisig_getpubkeys` retrieves public keys from the RPC parameters and `_createmultisig_getaddr_pubkeys` retrieves addresses' public keys from the wallet. `_createmultisig_getaddr_pubkeys` requires the wallet and is only used by `addwitnessaddress` (except when `createmultisig` is used in deprecated mode).
`addwitnessaddress`'s API is also changed. Instead of returning just an address, it now returns the same thing as `createmultisig`: a JSON object with two fields, address and redeemscript.
Tree-SHA512: a5796e41935ad5e47d8165ff996a8b20d5112b5fc1a06a6d3c7f5513c13e7628a4fd37ec30fde05d8b15abfed51bc250710140f6834b13f64d0a0e47a3817969