custom Debug impl for mix::Node and gateway::Node

[jstuczyn]

Description

Something that has been bothering me for quite a while. The auto derived Debug for mix::Node and gateway::Node. whenever you wanted to quickly print your node details to stdout you were slammed with detailed curve point information which in 99.99% cases is not what you want. Thus I've changed it to use stringified key details instead.

Long story short for println!("{gateway:#?}") instead of:

'Node {
    owner: "n1k5uwsuewkqhf3s6n5zx9ps2wkdgs9p9fhcdujn",
    host: IpAddr(
        85.159.212.96,
    ),
    mix_host: 85.159.212.96:1789,
    clients_port: 9000,
    identity_key: PublicKey(
        PublicKey(CompressedEdwardsY: [106, 216, 165, 242, 138, 74, 126, 89, 190, 83, 92, 199, 158, 188, 152, 77, 224, 215, 117, 101, 122, 136, 49, 133, 182, 48, 80, 217, 157, 164, 25, 60]), EdwardsPoint{
        	X: FieldElement51([401081558954162, 1119876266921654, 519567740851975, 1272911700607453, 1376462587655230]),
        	Y: FieldElement51([1770810497161322, 1082931082152751, 1644180073243378, 100341588966706, 1057293338514691]),
        	Z: FieldElement51([1, 0, 0, 0, 0]),
        	T: FieldElement51([2240565687814151, 1279965419925540, 1672344571450002, 716923175485544, 446094628035297])
        }),
    ),
    sphinx_key: PublicKey(
        PublicKey(
            MontgomeryPoint(
                [
                    9,
                    62,
                    19,
                    206,
                    161,
                    63,
                    48,
                    94,
                    151,
                    136,
                    110,
                    224,
                    202,
                    91,
                    178,
                    245,
                    142,
                    162,
                    206,
                    14,
                    185,
                    70,
                    163,
                    35,
                    176,
                    109,
                    17,
                    70,
                    218,
                    237,
                    214,
                    66,
                ],
            ),
        ),
    ),
    version: Explicit(
        Version {
            major: 1,
            minor: 1,
            patch: 25,
            pre: [],
            build: [],
        },
    ),
}'

you will now be seeing

'gateway::Node {
    host: IpAddr(
        85.159.212.96,
    ),
    owner: "n1k5uwsuewkqhf3s6n5zx9ps2wkdgs9p9fhcdujn",
    mix_host: 85.159.212.96:1789,
    clients_port: 9000,
    identity_key: "8C5pc2dQyqVj6tksNQpfQs8LCSMzKjh7qUgwbfz3qo15",
    sphinx_key: "d5a7FETkQ6jCWpawEgpzJCT7iVipY3cMaBuut7ji9jP",
    version: Explicit(
        Version {
            major: 1,
            minor: 1,
            patch: 25,
            pre: [],
            build: [],
        },
    ),
}'

[octol]

Slammed is very accurate description :)
And yeah it's been annoying me to so kudos for sorting this out!