Add project with field images and their json config files (#3668)

fieldImages/src/main/native/include/fields/2021-barrel.h

@@ -0,0 +1,12 @@
+// 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
+
+#include <string_view>
+
+namespace fields {
+std::string_view GetResource_2021_barrelracingpath_json();
+std::string_view GetResource_2021_barrel_png();
+}  // namespace fields