Added method to set spawn location

By: SpeaKeasY <mekevin1917@gmail.com>

paper-api/src/main/java/org/bukkit/World.java

@@ -334,6 +334,13 @@ public interface World {
      */
     public Location getSpawnLocation();
 
+    /**
+     * Sets the spawn location of the world
+     * 
+     * @return True if it was successfully set.
+     */
+    public boolean setSpawnLocation(int x, int y, int z);
+
     /**
      * Gets the relative in-game time of this world.
      *