Add react router and required Webpack configs

src/components/NotFoundPage/NotFoundPage.scss

@@ -0,0 +1,6 @@
+.not-found-page {
+  text-align: center;
+  margin-top: 30vh;
+  font-size: 4rem;
+  font-weight: 200;
+}

src/components/NotFoundPage/NotFoundPage.tsx

@@ -0,0 +1,16 @@
+import * as React from "react";
+import "./NotFoundPage.scss";
+
+export interface NotFoundPageProps {}
+
+ class NotFoundPage extends React.Component<NotFoundPageProps, undefined> {
+  render() {
+    return (
+      <div className="not-found-page">
+        <strong>404</strong> | Ei vaan löydy
+      </div>
+    );
+  }
+}
+
+export default NotFoundPage;

src/components/NotFoundPage/index.ts

@@ -0,0 +1,2 @@
+import NotFoundPage from "./NotFoundPage";
+export default NotFoundPage;

src/index.tsx

@@ -1,7 +1,8 @@
 import * as React from "react";
 import {render} from "react-dom";
+import { BrowserRouter } from "react-router-dom";
 import {AppContainer} from "react-hot-loader";
-import App from "./components/App";
+import Routes from "./routes";
 import "normalize.css";
 import "./index.scss";
 
@@ -9,7 +10,9 @@ const rootEl = document.getElementById("root");
 
 render(
   <AppContainer>
-    <App/>
+    <BrowserRouter>
+      <Routes />
+    </BrowserRouter>
   </AppContainer>,
   rootEl
 );
@@ -18,12 +21,14 @@ render(
 declare const module: { hot: any };
 
 if (module.hot) {
-  module.hot.accept("./components/App", () => {
-    const NewApp = require("./components/App").default;
+  module.hot.accept("./routes", () => {
+    const NewRoutes = require("./routes").default;
 
     render(
       <AppContainer>
-        <NewApp/>
+        <BrowserRouter>
+          <NewRoutes />
+        </BrowserRouter>
       </AppContainer>,
       rootEl
     );

src/routes.tsx

@@ -0,0 +1,11 @@
+import * as React from "react";
+import { Switch, Route } from "react-router-dom";
+import App from "./components/App";
+import NotFoundPage from "./components/NotFoundPage";
+
+export default () => (
+  <Switch>
+    <Route exact path="/" component={App} />
+    <Route component={NotFoundPage} />
+  </Switch>
+);