Update vendor

vendor/github.com/go-openapi/swag/post_go18.go

@@ -0,0 +1,23 @@
+// 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.
+
+// +build go1.8
+
+package swag
+
+import "net/url"
+
+func pathUnescape(path string) (string, error) {
+	return url.PathUnescape(path)
+}