Initial public release of nearby library

Signed-off-by: Alexey Polyudov <apolyudov@google.com>
Change-Id: I85d490e448375aa4eb7b09680757c02fff1420b4

cpp/platform/port/string.h

@@ -0,0 +1,26 @@
+// Copyright 2020 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
+//
+//     https://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.
+
+#ifndef PLATFORM_PORT_STRING_H_
+#define PLATFORM_PORT_STRING_H_
+
+#include <string>
+
+#include "platform/port/config.h"
+
+#if NEARBY_USE_STD_STRING
+using std::string;
+#endif
+
+#endif  // PLATFORM_PORT_STRING_H_