0403e52ce3 Move the transaction hash types over to primitives (Tobin C. Harding)
7e454d756d Define extension traits for txid types (Tobin C. Harding)
832b726d03 Stop using all_zeros (Tobin C. Harding)
d69c241b5c Improve docs on associated consts (Tobin C. Harding)
68c9e28165 Do not use private constructor for txid hash types (Tobin C. Harding)
98328b5a7b Use as_byte_array to encode hash type (Tobin C. Harding)
Pull request description:
Move the `Txid` and `Wtxid` hash wrapper types over to `primitives`. This introduces to `primitves` an unconditional dependency on `hashes`.
ACKs for top commit:
Kixunil:
ACK 0403e52ce3
apoelstra:
ACK 0403e52ce3 successfully ran local tests
Tree-SHA512: d14fa95bc12c2399d30d4d640b5a3fce625d51adf587a8037158f7d7e7b6288170b2d4418ca2cb68f612086ea0bdd0fae3b577f84f0d60627072fdb2217a6531