Update frontend after user tests

[vitorgomateus]

• [x] group item types into usable media [audio, video, image, text, archival, unknown]
• [x] list browse items horizontally and add a title per aphabet
• [x] create labels with icons for each item type.
• [x] simplify access message.
• [x] highlight name, language, location, date, and description on series and item view.
• [x] group content into panels and make parent items panel always visible. Or find a better way to help users distinguish parent items from child items.