Styling loading indicator, removing unused routes, adding "getting started" explanation

Also, only update relative time every minute instead of 6 seconds. My bad

app/assets/javascripts/components/features/getting_started/index.jsx

@@ -0,0 +1,13 @@
+const GettingStarted = () => {
+  return (
+    <div className='static-content'>
+      <h1>Getting started</h1>
+      <p>Mastodon is still in development and one of the lacking areas at the moment is user discovery.</p>
+      <p>You can follow people if you know their username and the domain they are on by entering an e-mail-esque address into the form in the bottom of the sidebar.</p>
+      <p>If the target user is on the same domain as you, just the username will work. The same rule applies to mentioning people in statuses.</p>
+      <p>The developer of this project can be followed as Gargron@mastodon.social</p>
+    </div>
+  );
+};
+
+export default GettingStarted;