877f9af364 Add new hex parse error variant (Tobin C. Harding)
Pull request description:
Recently we used an error type that holds only one expected hex string length when parsing but for `PublicKey`s we have two (66 and 130). Add a new error variant to express the error. Requires adding a variant to `bip32` for the same thing.
Fix: #1281
ACKs for top commit:
Kixunil:
ACK 877f9af364
apoelstra:
ACK 877f9af364
Tree-SHA512: c1ca493ee30418bd82bc326b35c18731260e4217c371f37301a73c64f9a6631163801acc217c6c2c7b14f632a2ad5043174266c1b4fdce127698e68ab8494f20