Add snowpack as an example project. (#11)

* Initial tests set up

This adds tests using uvu (we can switch if people want) and restructures things a bit so that it's easier to test.

Like in snowpack you set up a little project. In our tests you can say:

```js
const result = await runtime.load('/blog/hello-world')
```

And analyze the result. I included a `test-helpers.js` which has a function that will turn HTML into a cheerio instance, for inspecting the result HTML.

* Bring snowpack example in

* Formatting

1 files changed, 31 insertions, 0 deletions

diff --git a/examples/snowpack/snowpack.config.js b/examples/snowpack/snowpack.config.js
new file mode 100644
index 000000000..5cab1aaa0
--- /dev/null
+++ b/examples/snowpack/snowpack.config.js
@@ -0,0 +1,31 @@
+/** @type {import("snowpack").SnowpackUserConfig } */
+module.exports = {
+  mount: {
+    public: '/',
+    //src: '/_dist_',
+  },
+  plugins: [
+    [
+      '@snowpack/plugin-sass', { compilerOptions: { style: 'compressed' } },
+    ],
+    '@snowpack/plugin-svelte',
+    '@snowpack/plugin-vue'
+  ],
+  packageOptions: {
+    // Blocked by CSS asset support
+    // source: 'remote',
+    // types: true,
+  },
+  devOptions: {
+    // Eleventy updates multiple files at once, so add a 1000ms delay before we trigger a browser update
+    hmrDelay: 1000,
+  },
+  buildOptions: {
+    out: '_site',
+  },
+  optimize: {
+    bundle: true,
+    minify: true,
+    target: 'es2018',
+  },
+};