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