Update to 2018_v4 image and new build system. (#598)

* Revert "Force OpenCV to 3.1.0 (#602)"

This reverts commit 50ed55e8e2.

* Removes Simulation

* Removes old build system

* Removes old gtest

* Adds new gmock and gtest

* Updates to new ni-libraries

* removes MyRobot (to be replaced)

* moves files to new location

* Adds new sim backend and new test executables

* updates .styleguide and .gitignore

* Changes cpp WPILibVersion to a function

MSVC throws an AV with the old version.

* Disables USBCamera on all systems except for linux

* 2018 NI Libraries

* New build system

wpilibc/src/main/native/include/Notifier.h

@@ -0,0 +1,64 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2008-2017. 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 <stdint.h>
+
+#include <atomic>
+#include <functional>
+#include <utility>
+
+#include "ErrorBase.h"
+#include "HAL/Notifier.h"
+#include "HAL/cpp/priority_mutex.h"
+
+namespace frc {
+
+typedef std::function<void()> TimerEventHandler;
+
+class Notifier : public ErrorBase {
+ public:
+  explicit Notifier(TimerEventHandler handler);
+
+  template <typename Callable, typename Arg, typename... Args>
+  Notifier(Callable&& f, Arg&& arg, Args&&... args)
+      : Notifier(std::bind(std::forward<Callable>(f), std::forward<Arg>(arg),
+                           std::forward<Args>(args)...)) {}
+
+  virtual ~Notifier();
+
+  Notifier(const Notifier&) = delete;
+  Notifier& operator=(const Notifier&) = delete;
+
+  void StartSingle(double delay);
+  void StartPeriodic(double period);
+  void Stop();
+
+ private:
+  // update the HAL alarm
+  void UpdateAlarm();
+  // HAL callback
+  static void Notify(uint64_t currentTimeInt, HAL_NotifierHandle handle);
+
+  // used to constrain execution between destructors and callback
+  static hal::priority_mutex m_destructorMutex;
+  // held while updating process information
+  hal::priority_mutex m_processMutex;
+  // HAL handle, atomic for proper destruction
+  std::atomic<HAL_NotifierHandle> m_notifier{0};
+  // address of the handler
+  TimerEventHandler m_handler;
+  // the absolute expiration time
+  double m_expirationTime = 0;
+  // the relative time (either periodic or single)
+  double m_period = 0;
+  // true if this is a periodic event
+  bool m_periodic = false;
+};
+
+}  // namespace frc