Switch SHA256 to BLAKE3 hash

[Owez]

Switching means greater speeds at the cost of having another library other then OpenSSL. At the time of issue opening, it was thought that switching OpenSSL to another library was needed, which is not the case.

[Owez]

This should be in 0.1.0-beta.2

Upon reopening, 0.1.0

[Owez]

Closing, not worth switching from OpenSSL due to the current lock-in effect unfortunately.

[Owez]

Reopening. The consensus on this is:

So 0.1.0 will have openssl for ed25519 only and then blake3 so i can keep compat
Then I just redo all the hashing mechanisms later without openssl, not breaking protocol or api compat

This means the upcoming 0.1.0 version will use openssl for only ED25519 and will also be using BLAKE3 as another dependency. This will then be fixed in a later version as a optimization to this library, without breaking api or protocol version compatibility.

[Owez]

Perhaps SHA3 (Keccak) would be better due to increased performance compared to BLAKE3 going forward