Add Grpc ProtoBuf support (request-response) (#1047)

* ProtoBuf

* .

* x

* ---

* x

* fx

* ...

* sc

* ...

* .

* groen

* x

* fix tests

* ok!?

* fix tests

* fix tests

* !

* x

* 6

* .

* x

* ivaluematcher

* transformer

* .

* sc

* .

* mapping

* x

* tra

* com

* ...

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* .

* .

* AddProtoDefinition

* .

* set

* grpahj

* .

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* IdOrText

* ...

* async

* async2

* .

* t

* nuget

* <PackageReference Include="ProtoBufJsonConverter" Version="0.2.0-preview-04" />

* http version

* tests

* .WithHttpVersion("2")

* <PackageReference Include="ProtoBufJsonConverter" Version="0.2.0" />

* HttpVersionParser

examples/WireMock.Net.Console.GrpcClient/greet.proto

@@ -0,0 +1,33 @@
+// Copyright 2019 The 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.
+
+syntax = "proto3";
+
+package greet;
+
+// The greeting service definition.
+service Greeter {
+  // Sends a greeting
+  rpc SayHello (HelloRequest) returns (HelloReply);
+}
+
+// The request message containing the user's name.
+message HelloRequest {
+  string name = 1;
+}
+
+// The response message containing the greetings
+message HelloReply {
+  string message = 1;
+}