Add support for motion controllers via the CemuHook controller input protocol.

This is done by:
1) Implementing said protocol in a new controller input class CemuHookUDPServer.
2) Adding functionality in the WiimoteEmu class for pushing that motion input to the emulated Wiimote and MotionPlus.
3) Suitably modifying the UI for configuring an Emulated Wii Remote.

Source/Core/DolphinQt/Config/Mapping/WiimoteEmuMotionControlIMU.h

@@ -0,0 +1,32 @@
+// Copyright 2019 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "DolphinQt/Config/Mapping/MappingWidget.h"
+
+class QCheckBox;
+class QFormLayout;
+class QGroupBox;
+class QHBoxLayout;
+class QLabel;
+class QVBoxLayout;
+
+class WiimoteEmuMotionControlIMU final : public MappingWidget
+{
+  Q_OBJECT
+public:
+  explicit WiimoteEmuMotionControlIMU(MappingWindow* window);
+
+  InputConfig* GetConfig() override;
+
+private:
+  void LoadSettings() override;
+  void SaveSettings() override;
+  void CreateMainLayout();
+  static QGroupBox* AddWarning(QGroupBox* groupbox);
+
+  // Main
+  QHBoxLayout* m_main_layout;
+};