Add signature hash annex support as per BIP-341#128

JAGADISHSUNILPEDNEKAR wants to merge 2 commits into

karask:masterkarask/python-bitcoin-utils:masterfrom

JAGADISHSUNILPEDNEKAR:signature-hash-annex-supportJAGADISHSUNILPEDNEKAR/python-bitcoin-utils:signature-hash-annex-supportCopy head branch name to clipboard