Switching back to SVG components for icons

No longer need the hack to only use them in components while URLs are
used in styles since I don't need icons in the styles anymore. Embedding
the markup also provides the option to restyle the icons

src/pages/404.js

@@ -4,10 +4,10 @@ import ReactDOM from 'react-dom';
 import '../style.css';
 
 import Message from '../components/Message';
-import errorIcon from 'feather-icons/dist/icons/alert-octagon.svg';
+import ErrorIcon from 'feather-icons/dist/icons/alert-octagon.svg';
 
 ReactDOM.render(
-  <Message icon={ errorIcon } heading="404 Page Not Found">
+  <Message icon={ ErrorIcon } heading="404 Page Not Found">
     <p>The page you have requested could not be found</p>
   </Message>,
   document.getElementById('root'));