Structure files create in 1.10.2 will not load in 1.11 under spigot.

Structure 'AirshipRib' is not available

They will load fine in vanilla single player

To reproduce:

1. Load spigot 1.10.2
2. save a structure file
3. load spigot 1.11
4. load structure file

How I tested it in singleplayer:

1. load spigot 1.10.2
2. save a structure file
3. transfer structure file to singleplayer world
4. load structure file