Add module resolver and refactor guide loading

lib/guide.js

@@ -0,0 +1,28 @@
+import guides from "data/guides";
+
+export const getRequestedGuide = req => {
+  const guide = guides.find(guide => guide.slug === req.url);
+  if (!guide) {
+    return null;
+  }
+
+  // Remove any slashes from the beginning
+  //   Webpack module resolver takes care of the base path
+  //   Look at `config.resolve.modules` in next.config.js
+  // Remove `.md` from the end
+  //   We need to put that in `require` below to make
+  //   webpack bundle all the markdown files
+  const path = guide.path.replace(/^\//, '').replace(/\.md$/, '');
+
+  try {
+    return {
+      ...guide,
+      component: require(`../${path}.md`).default,
+      // component: require(guide.path.replace(/^\//, '')).default
+    };
+  } catch (e) {
+    console.log(e);
+  }
+
+  return null;
+};