[datalogtool] Add datalogtool

This is a support tool for datalog file conversion (and eventually
download/remote datalog file management).

datalogtool/src/main/native/cpp/Exporter.h

@@ -0,0 +1,15 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#pragma once
+
+namespace glass {
+class Storage;
+}  // namespace glass
+
+void DisplayInputFiles();
+void DisplayEntries();
+void DisplayOutput(glass::Storage& storage);
+
+extern bool gShutdown;