Add (podman {image,manifest} push --sign-by-sigstore=param-file.yaml)

(podman push) and (podman manifest push) 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/skratchdot/open-golang/open/exec_windows.go

@@ -0,0 +1,33 @@
+// +build windows
+
+package open
+
+import (
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	// "syscall"
+)
+
+var (
+	cmd      = "url.dll,FileProtocolHandler"
+	runDll32 = filepath.Join(os.Getenv("SYSTEMROOT"), "System32", "rundll32.exe")
+)
+
+func cleaninput(input string) string {
+	r := strings.NewReplacer("&", "^&")
+	return r.Replace(input)
+}
+
+func open(input string) *exec.Cmd {
+	cmd := exec.Command(runDll32, cmd, input)
+	//cmd.SysProcAttr = &syscall.SysProcAttr{HideWindow: true}
+	return cmd
+}
+
+func openWith(input string, appName string) *exec.Cmd {
+	cmd := exec.Command("cmd", "/C", "start", "", appName, cleaninput(input))
+	//cmd.SysProcAttr = &syscall.SysProcAttr{HideWindow: true}
+	return cmd
+}