BIP 343: Mandatory activation of taproot deployment

This PR specifies a BIP 8(LOT=true) deployment to activate Taproot. Mandatory signaling would attempt to be enforced in approximately November 2022 (defined by block height) assuming the signaling threshold is not met before then. Original mailing list discussion: https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2021-April/018783.html

Specification