Adding EnlargeMode.

Some refactor and fixes.

src/EnlargeImages.js

@@ -0,0 +1,20 @@
+import Preferences from "./Preferences.js";
+import Styles from "./Styles.js";
+
+export default class EnlargeImages {
+
+    static STYLES_KEY = 'midefos-idealista-enlarge-images';
+
+    static apply() {
+        if (Preferences.get('enlargeImages')) {
+            this._addEnlargeImages();
+        } else {
+            Styles.remove(this.STYLES_KEY);
+        }
+    }
+
+    static _addEnlargeImages() {
+        Styles.add(Styles.ENLARGE_IMAGES, this.STYLES_KEY);
+    }
+
+}