Add sourcesecret and kustomization manifestgen

This includes a change to the `sync` generator to make the deploy
secret name configurable.

Signed-off-by: Hidde Beydals <hello@hidde.co>

pkg/manifestgen/kustomization/options.go

@@ -0,0 +1,33 @@
+/*
+Copyright 2021 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 kustomization
+
+import "sigs.k8s.io/kustomize/api/filesys"
+
+type Options struct {
+	FileSystem filesys.FileSystem
+	BaseDir    string
+	TargetPath string
+}
+
+func MakeDefaultOptions() Options {
+	return Options{
+		FileSystem: filesys.MakeFsOnDisk(),
+		BaseDir:    "",
+		TargetPath: "",
+	}
+}