Add support for references in window inflater

api/src/main/java/com/bartlomiejpluta/base/api/game/gui/window/Inflatable.java

@@ -0,0 +1,7 @@
+package com.bartlomiejpluta.base.api.game.gui.window;
+
+public interface Inflatable {
+   default void onInflate() {
+      // do nothing
+   }
+}

api/src/main/java/com/bartlomiejpluta/base/api/game/gui/window/Ref.java

@@ -0,0 +1,12 @@
+package com.bartlomiejpluta.base.api.game.gui.window;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target(ElementType.FIELD)
+@Retention(RetentionPolicy.RUNTIME)
+public @interface Ref {
+   String value();
+}