v1.4.0 - First GUI for GCodeClean

It's very basic - but it works

Please pay special attention to the installation requirements in the README.md file - this is a 'side-loaded' app - you can't find it in the Windows store.

For first time installation do not use GUI_1.4.0.0_x64.msix. Instead, right click on Install.ps1 and select Run with PowerShell. That's so the 'test' certificate can be installed before installing the app itself - side-loaded app remember.

Which brings up another point. Windows only at the moment. While there is config for iOS, macOS, and Android, all of that is currently 'turned off'. Please let me know if you can help with building the mac and iOS stuff if you need that.