WIP: Experimenting with Lager for Redux like implementation

cmake/ExternalProjectBackCompat.cmake

@@ -0,0 +1,10 @@
+# Provides backwards compatibility for FetchContent_MakeAvailable
+if(${CMAKE_VERSION} VERSION_LESS 3.14)
+    macro(FetchContent_MakeAvailable NAME)
+        FetchContent_GetProperties(${NAME})
+        if(NOT ${NAME}_POPULATED)
+            FetchContent_Populate(${NAME})
+            add_subdirectory(${${NAME}_SOURCE_DIR} ${${NAME}_BINARY_DIR})
+        endif()
+    endmacro()
+endif() 

cmake/TargetLinkSys.cmake

@@ -0,0 +1,29 @@
+# From https://stackoverflow.com/questions/52135983/cmake-target-link-libraries-include-as-system-to-suppress-compiler-warnings
+function(target_link_libraries_system target)
+  set(options PRIVATE PUBLIC INTERFACE)
+  cmake_parse_arguments(TLLS "${options}" "" "" ${ARGN})
+  foreach(op ${options})
+    if(TLLS_${op})
+      set(scope ${op})
+    endif()
+  endforeach(op)
+  set(libs ${TLLS_UNPARSED_ARGUMENTS})
+
+  foreach(lib ${libs})
+    get_target_property(lib_include_dirs ${lib} INTERFACE_INCLUDE_DIRECTORIES)
+    if(lib_include_dirs)
+      if(scope)
+        target_include_directories(${target} SYSTEM ${scope} ${lib_include_dirs})
+      else()
+        target_include_directories(${target} SYSTEM PRIVATE ${lib_include_dirs})
+      endif()
+    else()
+      message("Warning: ${lib} doesn't set INTERFACE_INCLUDE_DIRECTORIES. No include_directories set.")
+    endif()
+    if(scope)
+      target_link_libraries(${target} ${scope} ${lib})
+    else()
+      target_link_libraries(${target} ${lib})
+    endif()
+  endforeach()
+endfunction(target_link_libraries_system)