* Move X25519, X448, Ed25519 and Ed448 feature tests to module_utils.
* Correctly sign with Ed25519 and Ed448 keys.
* Fix public key comparison. Ed25519 and Ed448 do not have public_numbers().
* Add tests.
* Add changelog.
* Give better errors for cryptography 2.6.x and 2.7.x.
* Test for new errors.
* Forgot one.
* Used wrong private key.
* Use private key password for CA key. Add more stuff to its certificate.
