GUIUtility.systemCopyBuffer doesn't work in WebGL

- Icon placements & updates
- black border for panels
- "Rechtliches" Button link set

Reimported combined meshes
Deleted unused meshes and materials
Made use of material remapping

One texture and material for all static ribbons
Updated meshes with correct UVs
Updated script accordingly

If no exhibit in range, default hochschulInfos are displayed

ExtraLight Profname, Bigger "Ausstellende", Students from left to right

Text and icons are now one sprite

Load Animation is now bound to download progress

SA = StreamingAssets

If a room is not fully configured, it won't trigger the disabling of the model's ribbon and won't trigger the loading process. This way, the room can be entered and the ribbon will stay activated. This allows for texturizing the model's ribbons with leitsystem assets down the road, too.

SerializeField "distanceFromExhibit" for further tuning