Add support for Fulcio and Rekor, and --sign-by-sigstore=param-file

(skopeo copy) and (skopeo sync) now support --sign-by-sigstore=param-file,
using the containers-sigstore-signing-params.yaml(5) file format.

That notably adds support for Fulcio and Rekor signing.

Signed-off-by: Miloslav Trmač <mitr@redhat.com>

vendor/github.com/go-openapi/runtime/security/authorizer.go

@@ -0,0 +1,27 @@
+// Copyright 2015 go-swagger maintainers
+//
+// 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 security
+
+import (
+	"net/http"
+
+	"github.com/go-openapi/runtime"
+)
+
+// Authorized provides a default implementation of the Authorizer interface where all
+// requests are authorized (successful)
+func Authorized() runtime.Authorizer {
+	return runtime.AuthorizerFunc(func(_ *http.Request, _ interface{}) error { return nil })
+}