socket: Make closing work a little better

irc/socket.go

 func (socket *Socket) Close() {
 	socket.Closed = true
 
-	// 'send data' to force close loop to happen
-	socket.linesToSendMutex.Lock()
-	socket.linesToSend = append(socket.linesToSend, "")
-	socket.linesToSendMutex.Unlock()
+	// force close loop to happen
 	go socket.fillLineToSendExists()
 }
 
 		case <-socket.lineToSendExists:
 			socket.linesToSendMutex.Lock()
 
+			// check if we're closed
+			if socket.Closed {
+				break
+			}
+
 			// check sendq
 			var sendQBytes uint64
 			for _, line := range socket.linesToSend {