Add socks proxy

[wind-hx]

Test passed

[wind-hx]

demo

let proxyOptions = {
        host: '127.0.0.1',
        port: 7890,
        type: 5        // 5: socks5
}
let mtProto = new MTProto({
        api_id: apiId,
        api_hash: apiHash,
        storageOptions: {
            instance: storage
        },
        proxy: proxyOptions
    })