Add Forge DataFixer.

Unsure how useful this will be, but eh.

config/checkstyle/import-control.xml

@@ -57,6 +57,7 @@
       <allow pkg="io.netty.buffer"/>
       <allow pkg="org.spongepowered.api" />
       <allow pkg="com.mojang.brigadier" />
+      <allow pkg="com.mojang.datafixers" />
     </subpackage>
 
     <subpackage name="sponge">

worldedit-forge/src/main/java/com/sk89q/worldedit/forge/ForgePlatform.java

@@ -26,6 +26,7 @@ import com.sk89q.worldedit.extension.platform.Actor;
 import com.sk89q.worldedit.extension.platform.Capability;
 import com.sk89q.worldedit.extension.platform.MultiUserPlatform;
 import com.sk89q.worldedit.extension.platform.Preference;
+import com.sk89q.worldedit.world.DataFixer;
 import com.sk89q.worldedit.world.World;
 import com.sk89q.worldedit.world.registry.Registries;
 import net.minecraft.command.Commands;
@@ -53,11 +54,13 @@ class ForgePlatform extends AbstractPlatform implements MultiUserPlatform {
 
     private final ForgeWorldEdit mod;
     private final MinecraftServer server;
+    private final ForgeDataFixer dataFixer;
     private boolean hookingEvents = false;
 
     ForgePlatform(ForgeWorldEdit mod) {
         this.mod = mod;
         this.server = ServerLifecycleHooks.getCurrentServer();
+        this.dataFixer = new ForgeDataFixer(getDataVersion());
     }
 
     boolean isHookingEvents() {
@@ -75,6 +78,11 @@ class ForgePlatform extends AbstractPlatform implements MultiUserPlatform {
         return 1631;
     }
 
+    @Override
+    public DataFixer getDataFixer() {
+        return dataFixer;
+    }
+
     @Override
     public boolean isValidMobType(String type) {
         return net.minecraftforge.registries.ForgeRegistries.ENTITIES.containsKey(new ResourceLocation(type));