Wrong ASN.1 description for ed25519-sha-256

[r-marques]

In the version 02 of the draft the condition and fulfillment ASN.1 representation for ed25519 is switched. https://github.com/rfcs/crypto-conditions/blob/draft-02/src/spec/crypto-conditions.md#asn1-ed25519-sha-256-condition-asn1

The condition fingerprint is describing the fulfillment and the fulfillment is describing the fingerprint

### ASN.1 {#ed25519-sha-256-condition-asn1}

    -- Condition Fingerprint
    Ed25519Sha512Fulfillment ::= SEQUENCE {
      publicKey            OCTET STRING (SIZE(32)),
      signature            OCTET STRING (SIZE(64))
    }

    -- Fulfillment 
    Ed25519FingerprintContents ::= SEQUENCE {
      publicKey            OCTET STRING (SIZE(32))
    }

[adrianhopebailie]

Fixed in #23