Visiting url

Initial PR to get PR number for changelog.
@oliverbarnes I think @KatiRG described it accurately, `IssuesIndex` is not used for displaying anything, it's just there to reset things.

> Is there some other way to set expandedIssueId to null in IssuesRoute?

Now when I think about it, deactivate hook could work, but I'm not 100% sure about this, so you would have to check. In `routes/issues/issue.js`:

```javascript
var IssueRoute = Ember.Route.extend({
  model: function(params) {
    return this.store.find('issue', params.issue_id);
  },
  setupController: function(controller, model) {
    this._super(controller, model);

    this.controllerFor('issues').set('expandedIssueId', model.get('id'));
  },

  renderTemplate: function() {
    // just do nothing
  },

  deactivate: function() {
    this.controllerFor('issues').set('expandedIssueId', null);
  }
});

export default IssueRoute;
```