Navigate when <dialog> element closes

For comparison [see this commit][commit]

This higlights the previous commit's comment on reverting the state with
`history.back`. This feature was easier to implement because Superglue stores the
previous pages state in the Redux store, and if it doesn't exist the browser
will fallback to doing a full refresh.

[commit]: seanpdoyle@c7613b1

app/components/Dialog.js

@@ -20,7 +20,7 @@ export default class extends React.Component {
 
   render () {
     return (
-      <dialog className='syos-dialog' ref={this.dialog}>
+      <dialog className='syos-dialog' ref={this.dialog} onClose={() => history.back()}>
         {this.props.children}
       </dialog>
     )