The PR changes the color palette of the editor to be darker (inspired by the "Dark Modern" theme of Visual Studio Code).

It also replaces all 16*16 pixel PNG icons with SVG icons. The UI for components gets a colored border, the color represents the category of each component (thanks to @PlasmaDev5 for the original idea and implementation) . The shape icons in the viewport similarly use a variation of that color for a more consistent design language.

Overall this is a first step for revamping the UI, especially to get rid of the old, tiny PNG icons. If you have ideas for improvements, please share them. Not all icons are great, but there were over 300 that needed to be adjusted, so priority was to get this done, at all, not to get it to be perfect. Similarly for the color scheme. I reused variations of the existing color scheme colors (see ezColorScheme) to stay consistent, but what each color is used for and how they were chosen exactly, was mostly random. If someone has a better understanding of design, please feel free to tinker with it and open follow up PRs.

For reference, all SVG icons were taken from https://www.svgrepo.com. They are all free, but some require attribution. I will add those to our documentation soon.