* skeleton of spirograph
* add graphics to cmake
* updating DIRECTORY.md
* added cmake to graphics folder
* add stub test function
* working program
* set pre-processor macro if GLUT is available
* use snprintf
details: http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1967.htm
* conditional include for mac
* corrected conditional include for mac
* fix cmake for MACOS
* OpenGL animation if available, else plot to CSV
* MacOS does not provide glutBitmapString function
* formatting source-code for 8d570b4c28
* fix parameter
* try caps include path GL
* provide custom glutBitmapString cuntion
* add glut library to gitpod docker
* enable VNC in gitpod
* better documentation and cmake configuration
* enable keyboard inputs to pause and change parameters
* fix lgtm alerts
* implementation similar to one in C++ repo
* fix compilation errors on MSVC
Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>