Add preliminary GRPC server for PyBullet and BulletRobotics.

Will add GRPC client and PyBullet GRPC server plugin.
Will cover most/all SharedMemoryCommand/SharedMemoryStatus messages.
Run the server, then test using the pybullet_client.py

examples/SharedMemory/grpc/pybullet.grpc.pb.cpp

@@ -0,0 +1,59 @@
+// Generated by the gRPC C++ plugin.
+// If you make any local change, they will be lost.
+// source: pybullet.proto
+
+#include "pybullet.pb.h"
+#include "pybullet.grpc.pb.h"
+
+#include <grpc++/impl/codegen/async_stream.h>
+#include <grpc++/impl/codegen/async_unary_call.h>
+#include <grpc++/impl/codegen/channel_interface.h>
+#include <grpc++/impl/codegen/client_unary_call.h>
+#include <grpc++/impl/codegen/method_handler_impl.h>
+#include <grpc++/impl/codegen/rpc_service_method.h>
+#include <grpc++/impl/codegen/service_type.h>
+#include <grpc++/impl/codegen/sync_stream.h>
+namespace pybullet_grpc {
+
+static const char* PyBulletAPI_method_names[] = {
+  "/pybullet_grpc.PyBulletAPI/SubmitCommand",
+};
+
+std::unique_ptr< PyBulletAPI::Stub> PyBulletAPI::NewStub(const std::shared_ptr< ::grpc::ChannelInterface>& channel, const ::grpc::StubOptions& options) {
+  std::unique_ptr< PyBulletAPI::Stub> stub(new PyBulletAPI::Stub(channel));
+  return stub;
+}
+
+PyBulletAPI::Stub::Stub(const std::shared_ptr< ::grpc::ChannelInterface>& channel)
+  : channel_(channel), rpcmethod_SubmitCommand_(PyBulletAPI_method_names[0], ::grpc::RpcMethod::NORMAL_RPC, channel)
+  {}
+
+::grpc::Status PyBulletAPI::Stub::SubmitCommand(::grpc::ClientContext* context, const ::pybullet_grpc::PyBulletCommand& request, ::pybullet_grpc::PyBulletStatus* response) {
+  return ::grpc::BlockingUnaryCall(channel_.get(), rpcmethod_SubmitCommand_, context, request, response);
+}
+
+::grpc::ClientAsyncResponseReader< ::pybullet_grpc::PyBulletStatus>* PyBulletAPI::Stub::AsyncSubmitCommandRaw(::grpc::ClientContext* context, const ::pybullet_grpc::PyBulletCommand& request, ::grpc::CompletionQueue* cq) {
+  return new ::grpc::ClientAsyncResponseReader< ::pybullet_grpc::PyBulletStatus>(channel_.get(), cq, rpcmethod_SubmitCommand_, context, request);
+}
+
+PyBulletAPI::Service::Service() {
+  AddMethod(new ::grpc::RpcServiceMethod(
+      PyBulletAPI_method_names[0],
+      ::grpc::RpcMethod::NORMAL_RPC,
+      new ::grpc::RpcMethodHandler< PyBulletAPI::Service, ::pybullet_grpc::PyBulletCommand, ::pybullet_grpc::PyBulletStatus>(
+          std::mem_fn(&PyBulletAPI::Service::SubmitCommand), this)));
+}
+
+PyBulletAPI::Service::~Service() {
+}
+
+::grpc::Status PyBulletAPI::Service::SubmitCommand(::grpc::ServerContext* context, const ::pybullet_grpc::PyBulletCommand* request, ::pybullet_grpc::PyBulletStatus* response) {
+  (void) context;
+  (void) request;
+  (void) response;
+  return ::grpc::Status(::grpc::StatusCode::UNIMPLEMENTED, "");
+}
+
+
+}  // namespace pybullet_grpc
+