bug: non root html emit does not work

[lucacasonato]

A config that emits a HTML file like so:

    html({
      template: createHtmlTemplate,
      title: "React App",
      meta: [
        { charset: "utf-8" },
        {
          name: "viewport",
          content: "width=device-width, initial-scale=1",
        },
        {
          name: "description",
          content: "Web site created using create-react-app",
        },
      ],
      fileName: "x/test.html",
    }),

leads to three issues:

1. The emitted <script src="mod.js" type="module"></script> should look like <script src="../mod.js" type="module"></script>
2. The emitted <link href="mod.css" rel="stylesheet"> should look like <link href="../mod.css" rel="stylesheet">
3. mkdir -r dist/x has to be run before denopack, because denopack does not create the directory itself.

Meta

> denopack --version
denopack/0.8.0 linux-x86_64 deno-1.3.3

[Soremwar]

@jeroenptrs Dibs on this