Add initial migration to NextJS

lib/markdownToHtml.ts

@@ -0,0 +1,12 @@
+import remark from 'remark'
+import html from 'remark-html'
+// TODO: Create types
+const behead = require('remark-behead')
+
+export default async function markdownToHtml(markdown: string) {
+  const result = await remark()
+      .use(behead, { after: 0, depth: 1 })
+      .use(html)
+      .process(markdown)
+  return result.toString()
+}