Split up crypto/sha2
Add HMAC-SHA256
Add the RFC6979 PRNG
Deterministic signing
Header define style cleanups
Resize after succesful result
Merge pull request #5227

4cdaa95 Resize after succesful result (Pieter Wuille)
9d8604f Header define style cleanups (Pieter Wuille)
a53fd41 Deterministic signing (Pieter Wuille)
3060e36 Add the RFC6979 PRNG (Pieter Wuille)
a8f5087 Add HMAC-SHA256 (Pieter Wuille)
36fa4a7 Split up crypto/sha2 (Pieter Wuille)