Fix PEM header of RSA private keys

storage.go

@@ -171,7 +171,7 @@ func encodePrivateKey(key crypto.Signer) ([]byte, error) {
 	switch priv := key.(type) {
 	case *rsa.PrivateKey:
 		pb = &pem.Block{
-			Type:  "PRIVATE KEY",
+			Type:  "RSA PRIVATE KEY",
 			Bytes: x509.MarshalPKCS1PrivateKey(priv),
 		}
 	case *ecdsa.PrivateKey: