* Support sr25519 ecdh agreement * Align version of curve25519-dalek Co-authored-by: Jaco <jacogr@gmail.com> * Reduce code size Co-authored-by: Jaco <jacogr@gmail.com> * Add explicit tests on sr25519 key agreement * Fix linting issues * Fix sr25519 key_agreement test Co-authored-by: Jaco <jacogr@gmail.com>