Implements gif builder for animated favicon

[aurium]

Fixes #31

Changes

• Adds favicon module that builds gif animations and updates <link rel="icon">
  • the favicon.loading() accepts many parameters. The most important is the animation name.
  • It implements basic and ring-of-dots, copied from CSS animations.
  • The animation implementation is a simple frame drawer that receives all needed icon options and the frame index.
  • It depends on gif.js, and that was added to /public to load the web worker.
• Adds a favicon selector to the App component.

Screenshot/GIF

The animations are only a copy of existing ones. The most important is the way to do it.

Checks

• Passes linting
• Consistent look across browsers (Chrome do not supports animated gif favicon)