We'll allow api-10 to not be broke.

This needs a far better fix in 11 but that comes with looking over DataPack objects as a whole.

Signed-off-by: Chris Sanders <zidane@spongepowered.org>

src/main/java/org/spongepowered/api/world/WorldTypeTemplate.java

@@ -59,6 +59,13 @@ static Builder builder() {
         return Sponge.game().builderProvider().provide(Builder.class).reset();
     }
 
+    /**
+     * Returns the world type.
+     *
+     * @return The world type
+     */
+    WorldType worldType();
+
     interface Builder extends DataPackEntryBuilder<WorldType, WorldTypeTemplate, Builder> {
 
         <V> Builder add(Key<? extends Value<V>> key, V value);