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/components/loading_indicator.jsx

@@ -0,0 +1,13 @@
+const LoadingIndicator = () => {
+  const style = {
+    textAlign: 'center',
+    fontSize: '16px',
+    fontWeight: '500',
+    color: '#616b86',
+    paddingTop: '120px'
+  };
+
+  return <div style={style}>Loading...</div>;
+};
+
+export default LoadingIndicator;