jsonrpc: Return more info for validateaddress.

[JoeGruffins]

Add addressn, branch, and index returns so that a caller can determine
the HD path of an address when applicable. Also return more data for
not owned addresses when possible.

closes #2074

[JoeGruffins]

master

{
  "isvalid": false
}
{
  "isvalid": true,
  "address": "TkKkYvSrnu8orwhtedcJGkD7guarvZUbUAtjr4iKqD9Y8pNEf8iHu"
}
{
  "isvalid": true,
  "address": "Tsp18L8qTcjzigYXrD5GSdwDmhVYBpKmfUL"
}
{
  "isvalid": true,
  "address": "TkKnVfd6EvzEYAqiELWstkASHgVyYH8JK3gNvAxUX79C9CrnsV8W6"
}
{
  "isvalid": true,
  "address": "Tead9n1wLBgaUR7AZrrtt6WWeDfetbF3dpy"
}
{
  "isvalid": true,
  "address": "TkKpSQoKgxqfDPyXp3RTWk7ktTR69zn19vU1zHCdD18r9bMTvDKT3"
}
{
  "isvalid": true,
  "address": "TSs3jHQMbbZGPyftUh4cgaALzgDZhfXGtxn"
}
{
  "isvalid": true,
  "address": "TcvVou7ooM4rJRWNeJYwehJ9fQq1HTc5pbK"
}
{
  "isvalid": true,
  "address": "TkKkYvSrnu8orwhtedcJGkD7guarvZUbUAtjr4iKqD9Y8pNEf8iHu"
}
{
  "isvalid": true,
  "address": "TcfdqCrK2fiFJBZnGj5N6xs6rMsbQBsJBYf",
  "ismine": true,
  "isscript": true,
  "account": "imported",
  "addresses": [
    "Tsk7YBwMxAko9edC2EL4JfootfCZewErWJF"
  ],
  "hex": "c376a914d17043c104a57393aa7353e1510e39eab811e3db88ac",
  "script": "treasurygen-pubkeyhash"
}
{
  "isvalid": true,
  "address": "TcrzaAVMbFURm1PpukWru8yE2uBTjvQePoa",
  "ismine": true,
  "isscript": true,
  "account": "imported",
  "addresses": [
    "TkQ4yoYbKYRzu89ufDNqC3fnxvn82wFTUgbF1xdgMpmmqGU8sYKFx",
    "TkQ3saYQz1423EiRAST9Lj9UWp3UJT9q6JvZLmao2HSSjG1v2Lp4G"
  ],
  "hex": "522103d484eb60ad03549e731ae9045281f8ee14ff6ea11b697f32cde3d8a18992261b210342b0b9c0ecb53cb9761beb0d010bbf08b5049d2a4d3bea5d3a1d95eb664931cb52ae",
  "script": "multisig",
  "sigsrequired": 2
}
{
  "isvalid": true,
  "address": "TckSpBht36nMZgnDDjv7xaHUrgCyJpxQiLA",
  "ismine": true,
  "isscript": true,
  "account": "imported",
  "hex": "01",
  "script": "nonstandard"
}
{
  "isvalid": true,
  "address": "Tsd5gT95ezpcqp1M3mNe9r113zb8dURsebs",
  "ismine": true,
  "pubkeyaddr": "TkQ3NkMGY3xd8p133Pk4BsHv6MyoexjSfC5nnHdKHvrWS1sbqfXnq",
  "pubkey": "030139eb89b3c36f39f95e4630c0e7f6cc3fef62db56592b15bc475366d5822b29",
  "iscompressed": true,
  "account": "default"
}

this pr currently

{
  "isvalid": false,
  "script": "nonstandard"
}
{
  "isvalid": true,
  "address": "TkKkYvSrnu8orwhtedcJGkD7guarvZUbUAtjr4iKqD9Y8pNEf8iHu",
  "pubkeyaddr": "TkKkYvSrnu8orwhtedcJGkD7guarvZUbUAtjr4iKqD9Y8pNEf8iHu",
  "pubkey": "020000000000000000000000000000000000000000000000000000000000000001",
  "script": "pubkey"
}
{
  "isvalid": true,
  "address": "Tsp18L8qTcjzigYXrD5GSdwDmhVYBpKmfUL",
  "iscompressed": true,
  "script": "pubkeyhash"
}
{
  "isvalid": true,
  "address": "TkKnVfd6EvzEYAqiELWstkASHgVyYH8JK3gNvAxUX79C9CrnsV8W6",
  "pubkeyaddr": "TkKnVfd6EvzEYAqiELWstkASHgVyYH8JK3gNvAxUX79C9CrnsV8W6",
  "pubkey": "0000000000000000000000000000000000000000000000000000000000000000",
  "script": "pubkey-ed25519"
}
{
  "isvalid": true,
  "address": "Tead9n1wLBgaUR7AZrrtt6WWeDfetbF3dpy",
  "iscompressed": true,
  "script": "pubkeyhash-ed25519"
}
{
  "isvalid": true,
  "address": "TkKpSQoKgxqfDPyXp3RTWk7ktTR69zn19vU1zHCdD18r9bMTvDKT3",
  "pubkeyaddr": "TkKpSQoKgxqfDPyXp3RTWk7ktTR69zn19vU1zHCdD18r9bMTvDKT3",
  "pubkey": "020000000000000000000000000000000000000000000000000000000000000001",
  "script": "pubkey-schnorr-secp256k1"
}
{
  "isvalid": true,
  "address": "TSs3jHQMbbZGPyftUh4cgaALzgDZhfXGtxn",
  "iscompressed": true,
  "script": "pubkeyhash-schnorr-secp256k1"
}
{
  "isvalid": true,
  "address": "TcvVou7ooM4rJRWNeJYwehJ9fQq1HTc5pbK",
  "isscript": true,
  "iscompressed": true,
  "script": "scripthash"
}
{
  "isvalid": true,
  "address": "TkKkYvSrnu8orwhtedcJGkD7guarvZUbUAtjr4iKqD9Y8pNEf8iHu",
  "pubkeyaddr": "TkKkYvSrnu8orwhtedcJGkD7guarvZUbUAtjr4iKqD9Y8pNEf8iHu",
  "pubkey": "020000000000000000000000000000000000000000000000000000000000000001",
  "script": "pubkey"
}
{
  "isvalid": true,
  "address": "TcfdqCrK2fiFJBZnGj5N6xs6rMsbQBsJBYf",
  "ismine": true,
  "isscript": true,
  "iscompressed": true,
  "account": "imported",
  "addresses": [
    "Tsk7YBwMxAko9edC2EL4JfootfCZewErWJF"
  ],
  "hex": "c376a914d17043c104a57393aa7353e1510e39eab811e3db88ac",
  "script": "treasurygen-pubkeyhash"
}
{
  "isvalid": true,
  "address": "TcrzaAVMbFURm1PpukWru8yE2uBTjvQePoa",
  "ismine": true,
  "isscript": true,
  "iscompressed": true,
  "account": "imported",
  "addresses": [
    "TkQ4yoYbKYRzu89ufDNqC3fnxvn82wFTUgbF1xdgMpmmqGU8sYKFx",
    "TkQ3saYQz1423EiRAST9Lj9UWp3UJT9q6JvZLmao2HSSjG1v2Lp4G"
  ],
  "hex": "522103d484eb60ad03549e731ae9045281f8ee14ff6ea11b697f32cde3d8a18992261b210342b0b9c0ecb53cb9761beb0d010bbf08b5049d2a4d3bea5d3a1d95eb664931cb52ae",
  "script": "multisig",
  "sigsrequired": 2
}
{
  "isvalid": true,
  "address": "TckSpBht36nMZgnDDjv7xaHUrgCyJpxQiLA",
  "ismine": true,
  "isscript": true,
  "iscompressed": true,
  "account": "imported",
  "hex": "01",
  "script": "nonstandard"
}
{
  "isvalid": true,
  "address": "TsfWQ6ocycevDFJu7A1JyBzxEu7M6ppW5Un",
  "ismine": true,
  "pubkeyaddr": "TkKkmUnuTQBsU5n99f9GsZPRRtxexvaMtbTgMuzv1RKPL4UGXjbd3",
  "pubkey": "021c83857e15870e77d4f2855886edc188f98f85b5f093d813a44a25461c717855",
  "iscompressed": true,
  "account": "default",
  "script": "pubkeyhash",
  "accountn": 0,
  "branch": 0,
  "index": 56
}

One subtle change that may or may not be welcome is that "script": "nonstandard" is set for invalid addresses. Not needed?

One thing I think should be changed is that "address" just returns whatever you put in. Because we have the "pubkeyaddr" field separately, it would make more sense to me if a query for a pubkey returned the encoded pubkeyhash address there. Or had a new "pubkeyhash" field, otherwise there is not a simple way to know what it is using rpc commands I beleive.

[jrick]

One subtle change that may or may not be welcome is that "script": "nonstandard" is set for invalid addresses. Not needed?

I don't see this as an issue