Docs redesign (#728)

* Adding a dark mode
* Adding reference for types to summary pages
* Adding API Reference
* Adding modifiers to methods/fields/etc
* Minimizing files input
* Caching a lot of the output pages
* Cache only for each execution
* Adding API references to existing docs

docs/input/api/Sections/_Summary.cshtml

@@ -0,0 +1,7 @@
+@{
+    var summary = Document.GetString("Summary");
+    if (!summary.IsNullOrWhiteSpace())
+    {
+        <div class="my-4 md:my-8">@Html.Raw(summary)</div>
+    }
+}