[examples/data-literate][m]: factor our a working markdown+CSV (data literate) example from site (where we already had a demo).

* removed a few extraneous things
* added the README.md with some instructions

examples/data-literate/components/DataLiterate.js

@@ -0,0 +1,45 @@
+import Layout from '../components/Layout'
+
+import { MDXRemote } from 'next-mdx-remote'
+import dynamic from 'next/dynamic'
+import Head from 'next/head'
+import Link from 'next/link'
+
+import { Vega, VegaLite } from 'react-vega'
+
+// Custom components/renderers to pass to MDX.
+// Since the MDX files aren't loaded by webpack, they have no knowledge of how
+// to handle import statements. Instead, you must include components in scope
+// here.
+const components = {
+  Table: dynamic(() => import('../components/Table')),
+  Excel: dynamic(() => import('../components/Excel')),
+  // TODO: try and make these dynamic ...
+  Vega: Vega,
+  VegaLite: VegaLite,
+  LineChart: dynamic(() => import('../components/LineChart')),
+  Head,
+}
+
+export default function DataLiterate({ children, source, frontMatter }) {
+  return (
+    <Layout title={frontMatter.title}>
+      <div className="prose mx-auto">
+        <header>
+          <div className="mb-6">
+            <h1>{frontMatter.title}</h1>
+            {frontMatter.author && (
+              <div className="-mt-6"><p className="opacity-60 pl-1">{frontMatter.author}</p></div>
+            )}
+            {frontMatter.description && (
+              <p className="description">{frontMatter.description}</p>
+            )}
+          </div>
+        </header>
+        <main>
+          <MDXRemote {...source} components={components} />
+        </main>
+      </div>
+    </Layout>
+  )
+}