Incoming vests delegation api call

Solves #26 (closed)

test suite:

cli_wallet:

transfer_to_vesting "initminer" "initminer" "100000.000 TESTS" true
create_account "initminer" "testnet" "" true
create_account "initminer" "howo" "" true
create_account "initminer" "netuoso" "" true
create_account "initminer" "test1" "" true
create_account "initminer" "test2" "" true
create_account "initminer" "theycallmedan" "" true
create_account "initminer" "hiveblog" "" true
create_account "initminer" "testing" "" true
create_account "initminer" "aaa" "" true
create_account "initminer" "bbb" "" true

transfer_to_vesting "initminer" "testnet" "10000.000 TESTS" true
transfer_to_vesting "initminer" "howo" "10000.000 TESTS" true
transfer_to_vesting "initminer" "netuoso" "10000.000 TESTS" true
transfer_to_vesting "initminer" "blocktrades" "10000.000 TESTS" true
transfer_to_vesting "initminer" "test2" "10000.000 TESTS" true
transfer_to_vesting "initminer" "theycallmedan" "10000.000 TESTS" true
transfer_to_vesting "initminer" "hiveblog" "10000.000 TESTS" true
transfer_to_vesting "initminer" "testing" "10000.000 TESTS" true
transfer_to_vesting "initminer" "aaa" "10000.000 TESTS" true
transfer_to_vesting "initminer" "bbb" "10000.000 TESTS" true




delegate_vesting_shares testnet netuoso "100.000000 VESTS" true
delegate_vesting_shares testnet blocktrades "100.000000 VESTS" true
delegate_vesting_shares testnet test2 "100.000000 VESTS" true
delegate_vesting_shares testnet theycallmedan "100.000000 VESTS" true
delegate_vesting_shares testnet testing "100.000000 VESTS" true

delegate_vesting_shares initminer howo "300.000000 VESTS" true
delegate_vesting_shares testnet howo "100.000000 VESTS" true
delegate_vesting_shares aaa howo "100.000000 VESTS" true
delegate_vesting_shares bbb howo "100.000000 VESTS" true
delegate_vesting_shares hiveblog howo "100.000000 VESTS" true

Js:

const rp = require('request-promise');

function find_incoming_vesting_delegations(account, limit, order) {
    return new Promise(async resolve => {
        if (!limit) {
            limit = 1000;
        }

        let result = (await rp({
            method: 'POST',
            uri: "http://127.0.0.1:8090",
            body: {
                "jsonrpc": "2.0",
                "method": "database_api.list_vesting_delegations",
                "params": {"start": [account], "limit": limit, "order": order},
                "id": 1
            },
            json: true
        }));
        return resolve(result)
    });
}

async function main() {
    let delegations = await find_incoming_vesting_delegations("howo", 5, "by_delegation");
    let incoming_delegations = await find_incoming_vesting_delegations("howo", 5, "by_incoming_delegation");
    console.log(delegations)
    console.log(incoming_delegations)
}

main();