cartservice: Create genproto.sh (GoogleCloudPlatform#249)

* Add src/cartservice/genproto.sh

* Add grpc generation to cartservice/genproto.sh

* Remove grpc from cartservice/genproto.sh due to errors

Author: djmailhot

src/cartservice/generate_protos.bat src/cartservice/genproto.batsrc/cartservice/generate_protos.bat renamed to src/cartservice/genproto.bat

@@ -0,0 +1,26 @@
+#!/bin/bash -eu
+#
+# Copyright 2018 Google LLC
+#
+# 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.
+
+# Generate the C# code for .proto files
+set -e
+
+PROTODIR=../../pb
+
+# enter this directory
+CWD="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
+
+protoc --csharp_out=$CWD/grpc_generated -I $PROTODIR $PROTODIR/demo.proto
+