Update README: notify this tool is broken with supergfxctl 5.0.1 because '-P' and '-p' options always return 'none'

Improve error message

Add support checking for powerprofilectl and supergfxctl

Reorganize source code

Optimize imports to reduce memory footprint

Create LICENSE.md

Fix in README

Rework on alert message box style

Rework on style

Fix unnecessary print

Refactoring

Rework error handling

Remove notification system to message boxes. Add pending mode widget and menu redraw to handle menuitem geometry changes. Update stylesheet. Various fixes and updates. WIP on inherited stylesheets.

Add warning icon for alert messages

Name QIconLabel widgets to allow fine-styling in stylesheets