[wpilib] Add BooleanEvent/Trigger factories on HID classes (#4247)

wpilibNewCommands/src/main/native/cpp/frc2/command/button/CommandGenericHID.cpp

@@ -0,0 +1,11 @@
+// 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.
+
+#include "frc2/command/button/CommandGenericHID.h"
+
+using namespace frc2;
+
+Trigger CommandGenericHID::Button(int button, frc::EventLoop* loop) const {
+  return GenericHID::Button(button, loop).CastTo<Trigger>();
+}