Rename "auto" subcommands to "image"

This means all the sub-subcommands can drop the `image-` prefix,
making them shorter and more fluent.

E.g.,

    flux create image policy

rather than

    flux create auto image-policy

Signed-off-by: Michael Bridgen <michael@weave.works>

cmd/flux/reconcile_image_repository.go

@@ -0,0 +1,50 @@
+/*
+Copyright 2020 The Flux authors
+
+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 (
+	"fmt"
+
+	"github.com/spf13/cobra"
+
+	imagev1 "github.com/fluxcd/image-reflector-controller/api/v1alpha1"
+)
+
+var reconcileImageRepositoryCmd = &cobra.Command{
+	Use:   "repository [name]",
+	Short: "Reconcile an ImageRepository",
+	Long:  `The reconcile image repository command triggers a reconciliation of an ImageRepository resource and waits for it to finish.`,
+	Example: `  # Trigger an scan for an existing image repository
+  flux reconcile image repository alpine
+`,
+	RunE: reconcileCommand{
+		names:  imageRepositoryNames,
+		object: imageRepositoryAdapter{&imagev1.ImageRepository{}},
+	}.run,
+}
+
+func init() {
+	reconcileImageCmd.AddCommand(reconcileImageRepositoryCmd)
+}
+
+func (obj imageRepositoryAdapter) lastHandledReconcileRequest() string {
+	return obj.Status.GetLastHandledReconcileRequest()
+}
+
+func (obj imageRepositoryAdapter) successMessage() string {
+	return fmt.Sprintf("scan fetched %d tags", obj.Status.LastScanResult.TagCount)
+}