1. update clientset, deepcopy using code-generator

2. add a dummy file tools.go to force "go mod vendor" to see
code-generator as dependencies
3. add a script to update CRD
4. add a README to document CRD updating steps
run go mod tidy
update README

vendor/gonum.org/v1/gonum/graph/topo/topo.go

@@ -0,0 +1,68 @@
+// Copyright ©2014 The Gonum 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 topo
+
+import (
+	"gonum.org/v1/gonum/graph"
+	"gonum.org/v1/gonum/graph/traverse"
+)
+
+// IsPathIn returns whether path is a path in g.
+//
+// As special cases, IsPathIn returns true for a zero length path or for
+// a path of length 1 when the node in path exists in the graph.
+func IsPathIn(g graph.Graph, path []graph.Node) bool {
+	switch len(path) {
+	case 0:
+		return true
+	case 1:
+		return g.Node(path[0].ID()) != nil
+	default:
+		var canReach func(uid, vid int64) bool
+		switch g := g.(type) {
+		case graph.Directed:
+			canReach = g.HasEdgeFromTo
+		default:
+			canReach = g.HasEdgeBetween
+		}
+
+		for i, u := range path[:len(path)-1] {
+			if !canReach(u.ID(), path[i+1].ID()) {
+				return false
+			}
+		}
+		return true
+	}
+}
+
+// PathExistsIn returns whether there is a path in g starting at from extending
+// to to.
+//
+// PathExistsIn exists as a helper function. If many tests for path existence
+// are being performed, other approaches will be more efficient.
+func PathExistsIn(g graph.Graph, from, to graph.Node) bool {
+	var t traverse.BreadthFirst
+	return t.Walk(g, from, func(n graph.Node, _ int) bool { return n.ID() == to.ID() }) != nil
+}
+
+// ConnectedComponents returns the connected components of the undirected graph g.
+func ConnectedComponents(g graph.Undirected) [][]graph.Node {
+	var (
+		w  traverse.DepthFirst
+		c  []graph.Node
+		cc [][]graph.Node
+	)
+	during := func(n graph.Node) {
+		c = append(c, n)
+	}
+	after := func() {
+		cc = append(cc, []graph.Node(nil))
+		cc[len(cc)-1] = append(cc[len(cc)-1], c...)
+		c = c[:0]
+	}
+	w.WalkAll(g, nil, after, during)
+
+	return cc
+}