Added images for users. Fixed wrong argument to image_tag_for_user function.
Returning null if products are empty in fetch_products_for_user_id.
Restructured user profile. Showing a message if the user has no products.
Styles for user profile. Removed padding of header and section. Too bothersome and too fragile.
Fixed a bug where a loop would iterate over the first category twice.
Fixed horizontal padding of subtitles.
Commit merge results.