generator: update main() to use latest Watch()

[hongchaodeng]

ref: #45

[hongchaodeng]

Generated main.go:

package main

import (
	"context"

	sdk "github.com/coreos/operator-sdk/pkg/sdk"
	stub "github.com/coreos/memcached-operator/pkg/stub"
)

func main() {
	namespace := "default"
	sdk.Watch("apps/v1", "Deployment", namespace)
 	sdk.Handle(&stub.Handler{})
 	sdk.Run(context.TODO())
}

[hongchaodeng]

@hasbro17 @fanminshi

[hasbro17]

LGTM

[fanminshi]

let's go with this approach. lgtm