sidestr-header 0.1.0

Block headers for sidestr sidechains, following the parent chain's family: the stock 80-byte SHA-256d header and Bitcoin Knots' 164-byte v2 header with the tagged-hash-plus-BLAKE2b proof of work, compact targets, powLimit checks and the BIP-325 block data. no_std, RustCrypto only. A port of bitcoin-desktop/schema and siding by Melvin Carvalho.