Modularised our tinymce config and plugins

- Split everything into specific plugin/concern files to make things
  more managable. Means original component file is now simple and much
  of the core config is focused in one place.

resources/js/wysiwyg/plugins-imagemanager.js

@@ -0,0 +1,31 @@
+/**
+ * @param {Editor} editor
+ * @param {String} url
+ */
+function register(editor, url) {
+
+    // Custom Image picker button
+    editor.ui.registry.addButton('imagemanager-insert', {
+        title: 'Insert an image',
+        icon: 'image',
+        tooltip: 'Insert an image',
+        onAction() {
+            window.ImageManager.show(function (image) {
+                const imageUrl = image.thumbs.display || image.url;
+                let html = `<a href="${image.url}" target="_blank">`;
+                html += `<img src="${imageUrl}" alt="${image.name}">`;
+                html += '</a>';
+                editor.execCommand('mceInsertContent', false, html);
+            }, 'gallery');
+        }
+    });
+}
+
+
+/**
+ * @param {WysiwygConfigOptions} options
+ * @return {register}
+ */
+export function getPlugin(options) {
+    return register;
+}