Add skeleton for mkcmp

This PR adds a skeleton for mkcmp, a binary to compare the performance
of two versions of minikube. It adds a Makefile rule out/mkcmp which
builds the binary.

Makefile

@@ -551,3 +551,7 @@ site: site/themes/docsy/assets/vendor/bootstrap/package.js out/hugo/hugo
 	  --navigateToChanged \
 	  --ignoreCache \
 	  --buildFuture)
+
+.PHONY: out/mkcmp
+out/mkcmp:
+	GOOS=$(GOOS) GOARCH=$(GOARCH) go build -o $@ cmd/performance/main.go

cmd/performance/cmd/mkcmp.go

@@ -0,0 +1,48 @@
+/*
+Copyright 2016 The Kubernetes Authors All rights reserved.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cmd
+
+import (
+	"errors"
+	"fmt"
+	"os"
+
+	"github.com/spf13/cobra"
+)
+
+var rootCmd = &cobra.Command{
+	Use:   "mkcmp [path to first binary] [path to second binary]",
+	Short: "mkcmp is used to compare performance of two minikube binaries",
+	PersistentPreRunE: func(cmd *cobra.Command, args []string) error {
+		return validateArgs(args)
+	},
+	Run: func(cmd *cobra.Command, args []string) {
+		return
+	},
+}
+
+func validateArgs(args []string) error {
+	if len(args) != 2 {
+		return errors.New("mkcmp requries two minikube binaries to compare: mkcmp [path to first binary] [path to second binary]")
+	}
+	return nil
+}
+
+// Execute runs the mkcmp command
+func Execute() {
+	if err := rootCmd.Execute(); err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}

cmd/performance/main.go

@@ -0,0 +1,20 @@
+/*
+Copyright 2016 The Kubernetes Authors All rights reserved.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+    http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package main
+
+import "k8s.io/minikube/cmd/performance/cmd"
+
+func main() {
+	cmd.Execute()
+}