add basic readme (#1)

README.md

@@ -0,0 +1,21 @@
+# Elementary: HTML Templating in Pure Swift
+
+**A modern and efficient HTML rendering library - inspired by SwiftUI, built for the web.**
+
+This packages helps you serve [Elementary](https://swiftpackageindex.com/sliemeobn/elementary) HTML web apps with Hummingbird.
+
+Simply wrap `HTMLResponse` around your HTML content and return it from your routes.
+
+```swift
+import Hummingbird
+import HummingbirdElementary
+
+let router = Router()
+router.get("index") { _, _ in
+    HTMLResponse {
+        MyIndexPage()
+    }
+}
+```
+
+Check out the docs in the [Elementary repo](https://github.com/sliemeobn/elementary) for more information.