OpenClonk games in the server list

The live server list now finally includes OpenClonk games!

It’s still a bit rough around the edges, but should show all games reliably. Unfortunately, not all scenarios include title images, and the existing images still have the old material textures. So please contribute some new images!

Known issues right now:

- Special characters such as umlauts don’t show correctly.
- The connection symbol is broken and always shows “disconnected”.
- Updating OC games sometimes seems to stop on Firefox, but works fine on Chrome.

Future updates will:

- Provide an option to show OC/CR games only.
- Maybe distinguish between OC and CR games more clearly.

Why isn't there an icon indicating whether it's a CR or OC game tough?

The title image does already allow distinguishing between CR and OC games. We may add some additional marker for CR/OC.