New About page

@tellyworth, @dd32, and I compiled a list of the remaining tasks for #3046. To help with transparency and community feedback, I’ll repost those here as well.

• New logo page redesign – implementation done this week (@obenland)
• Navigation – decide on the design and implement (@obenland)
• Enable main theme on w.org (@dd32)
• Replace prefixed translation strings (@dd32)
• Decide how to keep new pages in sync, and implement (@dd32)
• Write a script to add pages to Rosetta sites (@dd32)
• Back up old About page images (@dd32)
• Find a way to add links to About page into main Rosetta navigation (@dd32)
• Make sure navigation works for extra child pages on Rosetta sites (@dd32)
• Decide on how to handle translated slugs, and implement (@dd32)