Update dependencies

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

vendor/google.golang.org/api/dns/v1beta2/dns-api.json

@@ -1,11 +1,11 @@
 {
  "kind": "discovery#restDescription",
- "etag": "\"YWOzh2SDasdU84ArJnpYek-OMdg/-Is_yhPVg7HpaWKB9XfiNffDrdw\"",
+ "etag": "\"-iA1DTNe4s-I6JZXPt1t1Ypy8IU/BsiZ-YiIV-O9qmPqfJlQJ6pD0co\"",
  "discoveryVersion": "v1",
  "id": "dns:v1beta2",
  "name": "dns",
  "version": "v1beta2",
- "revision": "20171019",
+ "revision": "20180119",
  "title": "Google Cloud DNS API",
  "description": "Configures and serves authoritative DNS records.",
  "ownerDomain": "google.com",
@@ -368,6 +368,13 @@
      "description": "Identifies what kind of resource this is. Value: the fixed string \"dns#managedZone\".",
      "default": "dns#managedZone"
     },
+    "labels": {
+     "type": "object",
+     "description": "User labels.",
+     "additionalProperties": {
+      "type": "string"
+     }
+    },
     "name": {
      "type": "string",
      "description": "User assigned name for this resource. Must be unique within the project. The name must be 1-63 characters long, must begin with a letter, end with a letter or digit, and only contain lowercase letters, digits or dashes."

vendor/google.golang.org/api/dns/v1beta2/dns-gen.go

@@ -528,6 +528,9 @@ type ManagedZone struct {
 	// string "dns#managedZone".
 	Kind string `json:"kind,omitempty"`
 
+	// Labels: User labels.
+	Labels map[string]string `json:"labels,omitempty"`
+
 	// Name: User assigned name for this resource. Must be unique within the
 	// project. The name must be 1-63 characters long, must begin with a
 	// letter, end with a letter or digit, and only contain lowercase