use electron 8 spellchecker instead of electron-spellchecker, WIP

src/public/javascripts/widgets/note_tree.js

@@ -120,10 +120,10 @@ export default class NoteTreeWidget extends TabAwareWidget {
 
                     node.setSelected(true);
 
-                    const notes = this.getSelectedNodes().map(node => { return {
+                    const notes = this.getSelectedNodes().map(node => ({
                         noteId: node.data.noteId,
                         title: node.title
-                    }});
+                    }));
 
                     data.dataTransfer.setData("text", JSON.stringify(notes));
 

src/public/javascripts/widgets/promoted_attributes.js

@@ -125,7 +125,7 @@ export default class PromotedAttributesWidget extends TabAwareWidget {
                         return;
                     }
 
-                    attributeValues = attributeValues.map(attribute => { return { value: attribute }; });
+                    attributeValues = attributeValues.map(attribute => ({ value: attribute }));
 
                     $input.autocomplete({
                         appendTo: document.querySelector('body'),

src/public/javascripts/widgets/type_widgets/text.js

@@ -114,12 +114,10 @@ export default class TextTypeWidget extends TypeWidget {
         const codeBlockLanguages =
             (await mimeTypesService.getMimeTypes())
                 .filter(mt => mt.enabled)
-                .map(mt => {
-                    return {
+                .map(mt => ({
                         language: mt.mime.toLowerCase().replace(/[\W_]+/g,"-"),
                         label: mt.title
-                    }
-                });
+                    }));
 
         // CKEditor since version 12 needs the element to be visible before initialization. At the same time
         // we want to avoid flicker - i.e. show editor only once everything is ready. That's why we have separate