New LinearColorEntity, string serialization fixed

js/entity/ISerializable.js

@@ -0,0 +1,15 @@
+export default class ISerializable {
+
+    #showAsString = false
+
+    isShownAsString() {
+        return this.#showAsString
+    }
+
+    /**
+     * @param {Boolean} v
+     */
+    setShowAsString(v) {
+        this.#showAsString = v
+    }
+}