Clear table after fetch from server

Clears the table of stories when fetching a new list of stories. This
seems a bit drastic, but it ensures that the state icons are updated
as well (instead of just the titles).

static/js/main.js

@@ -247,6 +247,7 @@ var StoryPage = React.createClass({
     loadStoriesFromServer: function() {
         $.get(this.props.url)
             .done(function(data) {
+                this.setState({data: []});
                 this.setState({data: data});
             }.bind(this));
     },