TransactionDocument: replace Vec fields by SmallVec

issuers, signatures : SmallVec<[T; 4]>
inputs, unlocks : SmallVec<[T; 32]>
outputs : SmallVec<[T; 8]>

Edited Feb 10, 2020 by Éloïs

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information