vendor deps

Change-Id: Ia5385cbe6b9d6c9ad6065b7d2c402ebe164246d0

vendor/github.com/kelseyhightower/envconfig/doc.go

@@ -0,0 +1,8 @@
+// Copyright (c) 2013 Kelsey Hightower. All rights reserved.
+// Use of this source code is governed by the MIT License that can be found in
+// the LICENSE file.
+
+// Package envconfig implements decoding of environment variables based on a user
+// defined specification. A typical use is using environment variables for
+// configuration settings.
+package envconfig