* Remove unnecessary tracking opt in check * Add intro modal tests * Add changelog entry * Add extra check to see if modal has previously been dismissed
* Use static images for nav intro modal * Add 2x images
* Add initial intro modal * Hide modal on dismissal * Add modal styling * Add modal page content * Update styles to match Figma designs * Replace video with gifs * Check if user is opted in to satisfy gdpr concerns * Add testing instructions and changelog notes * Handle PR feedback * Handle responsiveness * Dismiss modal when welcome modal is shown simultaneously * Update shared modal option constants