Add transformName to Attribute

[rossabaker]

Use case: code that adds a prefix to all the names in a Seq[Attribute[_]]. Attribute.apply(prefix + old.name, old.`type`) won't work, because there is no access to KeySelect[A].

[iRevive]

This one is binary compatible, I think?

The bin compact is broken in the upcoming release anyway 🙂

P.S. I guess we can have a release by the end of the current week.

[NthPortal]

the alternative to this is to add an AttributeKey.apply method that takes a name and an AttributeType—because AttributeType is sealed, this doesn't allow users to create invalid keys