net_uv: sockets should be writable during connection

lib/net_uv.js

@@ -365,6 +365,7 @@ Socket.prototype.connect = function(port /* [host], [cb] */) {
   timers.active(this);
 
   self._connecting = true;
+  self.writable = true;
 
   if (typeof host == 'string') {
     debug("connect: find host " + host);