Make primary nav slick

Make the sidebar not occupy the whole screen width. Also add transitions for sidebar opening/closing.

Set background to active item in primary navbar.

Split page into multiple components. Organize URLs as resource-oriented.

Also make layout mobile-responsive.

Extract data persistence and updates from views. Also use custom CSS files for theming.

Use basic infer map of Sequelize models. Implement local and server-side deletion of notes.

Make sure backup makes saving to local storage a priority.