Allow clicking on model name/title to expand/collapse

[DavidBiesack]

In the new Swagger-UI, one can click on an operation's verb or summary text, or a tag/category name/summary to expand/collapse the box/section.

However for models, one can only click on the small > (or V ) icon to expand/collapse the model to show its fields or example.

Please let me click on the title string and the "{...}" text as well -- it's much easier to hit, and also a more consistent user experience.

The popup (i.e. "#/definitions/Order") should also show up on all clickable elements (not just the title)