LogDog: Add Butler stream server package.

client/internal/logdog/butler/streamserver/namedPipe_windows.go

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package streamserver
+
+import (
+        "net"
+
+        log "github.com/luci/luci-go/common/logging"
+        "golang.org/x/net/context"
+        npipe "gopkg.in/natefinch/npipe.v2"
+)
+
+// NewNamedPipeServer instantiates a new Windows named pipe server instance.
+func NewNamedPipeServer(ctx context.Context, address string) StreamServer {
+        ctx = log.SetField(ctx, "address", address)
+        return createNamedPipeServer(ctx, func() (net.Listener, error) {
+                log.Debugf(ctx, "Creating Windows server socket Listener.")
+                return npipe.Listen(address)
+        })
+}