[feature request] Auto-load SVG components

Hey!
With Nuxt 2.13, we can auto-load components. I tried auto-loading the SVG components like this in nuxt.config.js
```js
  components: {
    extensions: ['vue', 'svg']
  }
```
But it doesn't work. (I put the SVG files in the components directory).

It would be great if SVG components were auto-loaded like regular Vue components! 😀