Show name if no email is present in UID and proposal for new "oneline" output format
In #227 (closed) we chose a "oneline" format to represent a key in a single line. Apparently not including an email address is more common than expected. It doesn't produce actual error if the email misses from the description but it creates confusion (see e.g. #325 (closed)).
Thus I suggest to include the "name"-part of the UID if no "email" is present.