Changes

Summary

1. SPIGOT-2903: Add Structure API (details)

Commit 6be36d3638f97e6e0dc053f3e0fd0e68e8ec93f0 by md_5 (md_5) SPIGOT-2903: Add Structure API
	src/main/java/org/bukkit/structure/package-info.java
	src/main/java/org/bukkit/structure/Structure.java
	src/main/java/org/bukkit/structure/StructureManager.java
	src/main/java/org/bukkit/structure/Palette.java
	src/main/java/org/bukkit/Bukkit.java
	src/main/java/org/bukkit/Server.java