Suggestion: option to transfer the donor's username to the recipient

[tuxayo]

The donor could choose to let it's username be transferred to the recipient.

Use case:
https://en.liberapay.com/davidrevoy/

Q: Can I get a credit written at the end of Pepper&Carrot if I donate via Liberapay ?
A: No, I can't get access to your name/nickname here, it's a limitation of the platform but also a feature: your donation are totally anonymous to me.

[Changaco]

This issue is a duplicate of #271.

[tuxayo]

Thanks, I didn't manage to phrase a search query that would find it.