Align dependency metadata with imports.

Gopkg.lock was out of date.

Author: Ramon Nogueira

Gopkg.lock

@@ -2,10 +2,6 @@
 # to avoid locking to a particular minor version which can cause dep to not be
 # able to find a satisfying dependency graph.
 
-[[constraint]]
-  name = "cloud.google.com/go"
-  version = ">=0.21.0"
-
 [[constraint]]
   branch = "master"
   name = "git.apache.org/thrift.git"
@@ -27,18 +23,10 @@
   branch = "master"
   name = "golang.org/x/net"
 
-[[constraint]]
-  branch = "master"
-  name = "golang.org/x/oauth2"
-
 [[constraint]]
   branch = "master"
   name = "google.golang.org/api"
 
-[[constraint]]
-  branch = "master"
-  name = "google.golang.org/genproto"
-
 [[constraint]]
   name = "google.golang.org/grpc"
   version = "1.11.3"