psbt 0.9.0

Partially signed bitcoin transaction v0-2 library (bip174, bip370, bip371)

PSBT implementation

Implements both v0 (BIP-174) and v2 (BIP-370) versions of PSBT specification.

Based on bitcoin PSBT implementation, but wraps it into new type system supporting v2 features and providing convenient functions to iterate over sets of transaction inputs/outputs and corresponding PSBT key maps.