PeginWitness check
Fix PeginWitness serialization (#168) * go mod tidy * add test for toHex serialization with peginWitness * add check for peginWitness in anyWitnessInput
Fix PeginWitness serialization (#168) * go mod tidy * add test for toHex serialization with peginWitness * add check for peginWitness in anyWitnessInput