message: Make Socks5() InterruptibleRecv() timeout/failures informative.
  Before:
  2016-05-16 06:10:45 ERROR: Error reading proxy response
  After:
  2016-05-16 06:10:45 Socks5() connect to k7s5d6jqig4ej4v4.onion:18333 failed: InterruptibleRecv() timeout or other failure
diff: @@ -319,7 +319,8 @@ static bool Socks5(const std::string& strDest, int port, const ProxyCredentials
  char pchRet1[2];
  if (!InterruptibleRecv(pchRet1, 2, SOCKS5_RECV_TIMEOUT, hSocket)) {
  CloseSocket(hSocket);
  - return error("Error reading proxy response");
  + LogPrintf("Socks5() connect to %s:%d failed: InterruptibleRecv() timeout or other failure\n", strDest, port);
  + return false;
  }
  if (pchRet1[0] != 0x05) {
  CloseSocket(hSocket);
  