Work on fixing entity ID mapping

core/src/io/anuke/mindustry/game/TypeID.java

@@ -0,0 +1,19 @@
+package io.anuke.mindustry.game;
+
+import io.anuke.arc.function.Supplier;
+import io.anuke.mindustry.entities.traits.TypeTrait;
+import io.anuke.mindustry.type.ContentType;
+
+public class TypeID extends MappableContent{
+    public final Supplier<? extends TypeTrait> constructor;
+
+    public TypeID(String name, Supplier<? extends TypeTrait> constructor){
+        super(name);
+        this.constructor = constructor;
+    }
+
+    @Override
+    public ContentType getContentType(){
+        return ContentType.typeid;
+    }
+}