* added REST proxy client implementing the DHT API * added optional support for push notifications through the proxy server, using the gorush REST API: https://github.com/appleboy/gorush#web-api * DhtRunner: now able to use DhtProxyClient as a DHT node * DhtRunner: can switch between local or proxy node during runtime * SockAddr: added methods to handle IPv6-mapped IPv4 addresses * iOS: handle SIGPIPE on UDP sockets by recreating sockets * fixed occasional crash during packet processing