Replace deprecated API usage in C++ examples

Since there is a new version of GearsBot using the new command-based
API, the old GearsBot is just removed.

PR #1842 is being included to verify this PR is correct.

wpilibcExamples/src/main/cpp/examples/GearsBot/include/commands/OpenClaw.h

@@ -1,22 +0,0 @@
-/*----------------------------------------------------------------------------*/
-/* Copyright (c) 2017-2018 FIRST. All Rights Reserved.                        */
-/* Open Source Software - may be modified and shared by FRC teams. The code   */
-/* must be accompanied by the FIRST BSD license file in the root directory of */
-/* the project.                                                               */
-/*----------------------------------------------------------------------------*/
-
-#pragma once
-
-#include <frc/commands/Command.h>
-
-/**
- * Opens the claw for one second. Real robots should use sensors, stalling
- * motors is BAD!
- */
-class OpenClaw : public frc::Command {
- public:
-  OpenClaw();
-  void Initialize() override;
-  bool IsFinished() override;
-  void End() override;
-};