Add description text to developer instance page

[cilki]

Some developers have descriptions in the description field which should be rendered on the instance page similar to the game synopsis.

[longhorn396]

These are displayed when they exist. @atrieder Could you make it look pretty?

[atrieder]

I pushed 212fcd303302df92e6a87284e4d45b8c6c880c93 earlier today, which styles the descriptions to appear like the game pages:

Does the above look ok?

[longhorn396]

It looks great