The GUI files are organized now based on broad categories:
containers Windows, layout helper controls, controls that contain
other controls.
controls Buttons, text boxes, and so forth.
core This contains base GUI code, like GuiControl and GuiCanvas.
editor Specialized editor controls.
game Game specific controls, like progress bars or HUD elements.
utility Controls with specialized, usually invisible, purposes.
The goal is to provide developers with hints about what purpose code serves,
so that they can easily work with and extend GUI controls.
