Implement metrics for Windows Nodes

This implements stats for windows nodes in a new package, winstats.
WinStats exports methods to get cadvisor like datastructures, however
with windows specific metrics. WinStats only gets node level metrics and
information, container stats will go via the CRI. This enables the
use of the summary api to get metrics for windows nodes.

vendor/github.com/lxn/win/header.go

@@ -0,0 +1,40 @@
+// Copyright 2012 The win Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build windows
+
+package win
+
+const (
+	HDF_SORTDOWN = 0x200
+	HDF_SORTUP   = 0x400
+)
+
+const (
+	HDI_FORMAT = 4
+)
+
+const (
+	HDM_FIRST   = 0x1200
+	HDM_GETITEM = HDM_FIRST + 11
+	HDM_SETITEM = HDM_FIRST + 12
+)
+
+const (
+	HDS_NOSIZING = 0x0800
+)
+
+type HDITEM struct {
+	Mask       uint32
+	Cxy        int32
+	PszText    *uint16
+	Hbm        HBITMAP
+	CchTextMax int32
+	Fmt        int32
+	LParam     uintptr
+	IImage     int32
+	IOrder     int32
+	Type       uint32
+	PvFilter   uintptr
+}