Renaming of contacts and family members

[windmueller]

Describe the feature
As the administrator of a family plan I can see all invited members by their e-mail address that not necessarily reflects the name of its owner. So I would like to have the ability to rename those contacts in order to make sharing easier. This should also be possible for other people I share photos with.

Alternatively, there could be an option to set my(!) name only for me. With that, people using ente would appear with their chosen name.