feat(logo): proposal for a new, modern logo

This logo is closer to the community-driven [original](https://github.com/voodootikigod/logo.js). It's without rounded corners, gradients and shadows and came with the original typo.

To use it properly on every website, it's now saved as a png and a optimzed svg as well. It's more flexible as the HTML/CSS version.

Feel free to use it. :smile: