0.3.0: Refactoring + API change

• compare changes to previous version (there's a LOT!)
• NOTE this is the same as 0.2.17!
  • updated to 0.3.0 to be better compliant with semantic versioning practice of updating the version number when making backwards INCOMPATIBLE changes (https://semver.org/)
• no change in functionality, just changes in how things work under the hood and how to instantiate instances and call methods
  • updated ListGenerator() -> ListCreator()
    • no python generators are used in this program, so renamed to avoid being misleading and avoid potential confusion
  • updated create_list() -> create_list_for()
    • this is a more clear and obvious name that clearly describes what the method does
  • everything else is under the hood changes to how functions are invoked, user input is checked, functions/variables are named, code is organized (whitespace), import statements are organized, and user input is loaded (via tuple packing into instance_attributes in init.py and unpacking when loaded into execute.logic())"