Recent springboard-made maps may have floating features at start

[sprunk]

Apparently springboard sets y = ground+5 or something like that. The features are still affected by gravity so they immediately fall down and thus it only affects the startbox placement phase, but that is when people might zoom in to look around.

Some tasks:

• check what maps are affected
• maybe do a gameside fix with a whitelist, or repack the maps
• fix springboard