rename more components and update references

src/components/lazyLoader/lazyLoaderIntersectionObserver.js

@@ -0,0 +1,67 @@
+/* eslint-disable indent */
+    export class LazyLoader {
+        constructor(options) {
+            this.options = options;
+        }
+
+        createObserver() {
+            const callback = this.options.callback;
+
+            const observer = new IntersectionObserver(
+                (entries) => {
+                    entries.forEach(entry => {
+                        callback(entry);
+                    },
+                    {rootMargin: '50%'});
+                });
+
+            this.observer = observer;
+        }
+
+        addElements(elements) {
+            let observer = this.observer;
+
+            if (!observer) {
+                this.createObserver();
+                observer = this.observer;
+            }
+
+            Array.from(elements).forEach(element => {
+                observer.observe(element);
+            });
+        }
+
+        destroyObserver() {
+            const observer = this.observer;
+
+            if (observer) {
+                observer.disconnect();
+                this.observer = null;
+            }
+        }
+
+        destroy() {
+            this.destroyObserver();
+            this.options = null;
+        }
+    }
+
+    function unveilElements(elements, root, callback) {
+        if (!elements.length) {
+            return;
+        }
+        const lazyLoader = new LazyLoader({
+            callback: callback
+        });
+        lazyLoader.addElements(elements);
+    }
+
+    export function lazyChildren(elem, callback) {
+        unveilElements(elem.getElementsByClassName('lazy'), elem, callback);
+    }
+
+/* eslint-enable indent */
+export default {
+    LazyLoader: LazyLoader,
+    lazyChildren: lazyChildren
+};