/wallet/allPublicKeys should display the key type

[paolocappelletti]

/wallet/allPublicKey response currently shows only the "publicKey" field of each key present in the wallet (see example below).
We should add a "type" attribute because since 0.3.0 the Schnorr keys are very similar in length to the standard 25519 keys (the last one in the example), and this can be misleading.

{
"result": {
"propositions": [
{
"publicKey": "076a9191a89fee51439600b0455db357a9899694d1cdad6a3c71bf65e6cce53280"
},
{
"publicKey": "a5b10622d70f094b7276e04608d97c7c699c8700164f78e16fe5e8082f4bb2ac"
},
{
"publicKey": "69b3651f12491652b388b71a098dffcbda148951145d77c1ed3bf25a4119e46f8b"
},
{
"publicKey": "cc6e61126f3a743ef9b964d11924f2fd9b171b59bd622942198fea026367f8efa6"
},
{
"publicKey": "4b773229713aff1fc01ced6529b95c138aac85552621417b2ec14ea0432e3fe3fb"
},
{
"publicKey": "275da903bc8e6e7839fd4c654069e1624620adb643ca91762fa1bffa05d70a3491"
},
{
"publicKey": "9f7cce0570669f09278074113577d7edd1ff6275d7d396023b909e48ccad4d9e35"
},
{
"publicKey": "00057038ecb3280693fbc0c794547ed5f4727af71a6d02bb0d56f955f913caadd5"
},
{
"publicKey": "5b53c232c3e8efb3ad25a5bb064a54bc8007b83d6e7591683cdc31d163c3f78e18"
},
{
"publicKey": "47286ba429e486767d35e79702206d1181894487f8d74550cb1eec3b0bd9b5f3"
},
{
"publicKey": "94ed9aa9928393fde71280023e1afcc2578cfbcb68bff90b6d2785dbbd6c7beb"
}
]
}
}