Bootstrap with basic create-react-app and typescript.

No real changes to it, and I'm avoiding the favicon and logos to avoid
burdening my git repository, but otherwise it's all here while I figure
out how to change things.

src/App.tsx

@@ -0,0 +1,26 @@
+import React from 'react';
+import logo from './logo.svg';
+import './App.css';
+
+function App() {
+  return (
+    <div className="App">
+      <header className="App-header">
+        <img src={logo} className="App-logo" alt="logo" />
+        <p>
+          Edit <code>src/App.tsx</code> and save to reload, Eli.
+        </p>
+        <a
+          className="App-link"
+          href="https://reactjs.org"
+          target="_blank"
+          rel="noopener noreferrer"
+        >
+          Learn React
+        </a>
+      </header>
+    </div>
+  );
+}
+
+export default App;