Add cmake project files for cpp/ directory and all relevant subdirecctories

+ Add Makefiles generated by CMake JIC make is preferred
+ Update cmake version, header comments, and project descriptions

cpp/opengl-invaders/CMakeLists.txt

@@ -0,0 +1,58 @@
+###############################################################################
+## Author: Shaun Reed                                                        ##
+## Legal: All Content (c) 2019 Shaun Reed, all rights reserved               ##
+##                                                                           ##
+## Contact: shaunrd0@gmail.com  | URL: www.shaunreed.com | GitHub: shaunrd0  ##
+###############################################################################
+
+# Define CMake version
+cmake_minimum_required(VERSION 3.16)
+
+project(       # Define project
+    invaders  # Project name
+    DESCRIPTION  "Space invaders remake using OpenGL and CPP"
+    LANGUAGES    CXX
+    )
+
+# Pass this to program to control debug output
+option (EXE_BUILD "Should we build the executable?" ON)
+
+add_library(             # Add Library
+    lib-invaders            # Library Name
+    "src/lib-invaders.cpp"  # Sources..
+    "src/lib-invaders.h"
+    )
+
+target_include_directories(        # When calling library, include a directory
+    lib-invaders                      # Library name
+    PUBLIC                           #
+    "${CMAKE_CURRENT_SOURCE_DIR}"  # Source directory of exe including our library
+    )
+
+if (EXE_BUILD)
+  set(BUILD_STATUS "Building default executable")
+  include(FindOpenGL)
+  include(FindGLUT)
+  include_directories(${OPENGL_INCLUDE_DIRS} ${GLUT_INCLUDE_DIR})
+
+  add_executable(         # Creating executable
+      invaders             # Exe name
+      "app/invaders.cpp"  # Exe Source(s)
+      )
+
+  # Link the executable with OpenGL libraries
+  target_link_libraries(  # Linking the exe to library
+      invaders        # Executable to link
+      PUBLIC          #
+      lib-invaders    # Library to link
+      ${OPENGL_LIBRARIES}
+      )
+
+  # Link the executable with OpenGL Utility Toolkit
+  target_link_libraries(  # Linking the exe to library
+      invaders        # Executable to link
+      PUBLIC          #
+      lib-invaders    # Library to link
+      ${GLUT_LIBRARIES}
+      )
+endif()