* Pass the `mode` through to snowpack
This allows the production packages to be prepared.
* Use snowpack 3.3.1
* Update path to prism loadComponents external ref
* Upgrade to snowpack 3.3.2
* Add support for syntax highlighting of code blocks
* Escape usage of backtick strings
* Add workspace root for snowpack
* Use prismjs/components as an external module
This adds astro/components/ and moves the Prism.astro component into there. So to use in a project you can do:
```html
---
import Prism from 'astro/components/Prism.astro';
---
<Prism lang="html" code={`<html> ... </html>`}
```
