Read proxy option in imapserver, instantiate a class in imaplibutil
using a self-defined keyword and a socket instance, and use this socket
instance to substitute the default socket instance used in imaplib2.
Signed-off-by: 夏恺(Xia Kai) <xiaket@gmail.com>
Signed-off-by: Nicolas Sebrecht <nicolas.s-dev@laposte.net>
d36209a305