replace "dep" with "go mod"

A simple "go mod init && go mod tidy && go mod vendor" was enough and
mostly seems to have picked the same revisions of the dependencies as
before. Notable exceptions are klog and gogo/protobuf.

vendor/google.golang.org/grpc/internal/binarylog/regenerate.sh

@@ -0,0 +1,33 @@
+#!/bin/bash
+# Copyright 2018 gRPC authors.
+#
+# 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.
+
+set -eux -o pipefail
+
+TMP=$(mktemp -d)
+
+function finish {
+  rm -rf "$TMP"
+}
+trap finish EXIT
+
+pushd "$TMP"
+mkdir -p grpc/binarylog/grpc_binarylog_v1
+curl https://raw.githubusercontent.com/grpc/grpc-proto/master/grpc/binlog/v1/binarylog.proto > grpc/binarylog/grpc_binarylog_v1/binarylog.proto
+
+protoc --go_out=plugins=grpc,paths=source_relative:. -I. grpc/binarylog/grpc_binarylog_v1/*.proto
+popd
+rm -f ./grpc_binarylog_v1/*.pb.go
+cp "$TMP"/grpc/binarylog/grpc_binarylog_v1/*.pb.go ../../binarylog/grpc_binarylog_v1/
+