Byron addresses should be double-encoded in CBOR

[agaffney]

When marshaling Byron addresses to CBOR, our resulting CBOR tag structure should be CBOR-encoded, and the result of that wrapped in a CBOR bytestring.

Current version (from a TX output):

                [
                    [
                        24_0(<<[
                            h'2be5e2a084010a6c41d705ab340427aaa4d791fcfbaeb6efe20c863f',
                            {
                                1: h'581c9b1771bd305e4a0067f2a1a9b035eb3a68aaebf1de166f8a7af365f0',
                            },
                            0,
                        ]>>),
                        1424379315_2,
                    ],
                    ...
                ],

Desired result:

                [
                    h'82d818584283581c2be5e2a084010a6c41d705ab340427aaa4d791fcfbaeb6efe20c863fa101581e581c9b1771bd305e4a0067f2a1a9b035eb3a68aaebf1de166f8a7af365f0001a54e64db3',
                    ...
                ],