implement checkbox filtering + timeline animations

src/componets/Timeline.js

@@ -4,12 +4,13 @@ export default class Timeline extends React.Component {
   constructor(props) {
     super(props);
     this.items = props.children;
+    this.classes = props.classes;
   }
 
   componentDidMount() {}
 
   render() {
-    return <div className="timeline">
+    return <div className={"timeline " + this.classes}>
         {this.items}
     </div>;
   }