4.50. kink/hash/SHA256

Bin hashing by SHA-256.

4.50.1. SHA256.hash(Bin)

`hash` returns the SHA-256 hash value of `Bin`.

`Bin` must be a bin val. The result is a 32-byte bin.

4.50.2. SHA256.new_hasher

`new_hasher` returns a new `bin_hasher` of SHA-256.

See kink/hash/BIN_HASHER for `bin_hasher` type.