prio 0.17.0

Implementation of the Prio aggregation system core: https://crypto.stanford.edu/prio/
Documentation
{
    "agg_param": "",
    "agg_result": 1,
    "agg_shares": [
        "afccf0c22c8901be",
        "1f96fa976d56026a",
        "359d14a56320fcd7"
    ],
    "ctx": "736f6d65206170706c69636174696f6e",
    "prep": [
        {
            "input_shares": [
                "afccf0c22c8901be040bc9d44987fd40085bf595185a34267ec8e975e8fdfa331abaaecc9d7104785e186102448192ad",
                "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f",
                "202122232425262728292a2b2c2d2e2f303132333435363738393a3b3c3d3e3f"
            ],
            "measurement": 1,
            "nonce": "000102030405060708090a0b0c0d0e0f",
            "out_shares": [
                [
                    "afccf0c22c8901be"
                ],
                [
                    "1f96fa976d56026a"
                ],
                [
                    "359d14a56320fcd7"
                ]
            ],
            "prep_messages": [
                ""
            ],
            "prep_shares": [
                [
                    "145aabe8608487ab66ff1e11a196662b0d268a8dbd2b01481daf7d190bf1b0b6",
                    "a595f97a41f0f5565abc07086ef01d5b3cb2629a3c534bd4dbd8f5187ad75aad",
                    "49105b9c5b8b82fd30916e72506a0c5679b07c05a3255a85103f30cfd5ab310e"
                ]
            ],
            "public_share": "",
            "rand": "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f202122232425262728292a2b2c2d2e2f303132333435363738393a3b3c3d3e3f404142434445464748494a4b4c4d4e4f505152535455565758595a5b5c5d5e5f"
        }
    ],
    "shares": 3,
    "verify_key": "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f"
}