Update dependencies

Among others, this updates minio-go, so that the new "eu-west-3" zone
for AWS is supported.

vendor/cloud.google.com/go/import_test.go

@@ -0,0 +1,61 @@
+// Copyright 2017 Google Inc. All Rights Reserved.
+//
+// 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 cloud
+
+import (
+	"go/parser"
+	"go/token"
+	"os"
+	"path/filepath"
+	"strconv"
+	"testing"
+)
+
+func TestContextImport(t *testing.T) {
+	t.Parallel()
+
+	whiteList := map[string]bool{
+		"storage/go17.go": true,
+	}
+
+	err := filepath.Walk(".", func(path string, fi os.FileInfo, err error) error {
+		if err != nil {
+			return err
+		}
+		if filepath.Ext(path) != ".go" || whiteList[path] {
+			return nil
+		}
+
+		fset := token.NewFileSet()
+		file, err := parser.ParseFile(fset, path, nil, parser.ImportsOnly)
+		if err != nil {
+			return err
+		}
+
+		for _, imp := range file.Imports {
+			impPath, err := strconv.Unquote(imp.Path.Value)
+			if err != nil {
+				return err
+			}
+			if impPath == "context" {
+				t.Errorf(`file %q import "context", want "golang.org/x/net/context"`, path)
+			}
+		}
+		return nil
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+}