MB-11804: Handle errors during connect in windows

Handle WSAEINPROGRESS and WSAEWOULDBLOCK errors while connecting
to a downstream connection

Change-Id: Ie573a67a937ce2c7c3c27243ebabd721691c51fe
Reviewed-on: http://review.couchbase.org/41065
Tested-by: Sriram Ganesan <sriram@couchbase.com>
Reviewed-by: Chiyoung Seo <chiyoung@couchbase.com>
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>