On the repository summary page, leave the owner line out if the
repo does not have an owner, rather than displaying a labelled empty
field. This does not affect the owner column in the projects list
page, which is present unless $omit_owner is true.
Signed-off-by: Tony Finch <dot@dotat.at> Signed-off-by: Junio C Hamano <gitster@pobox.com>