gitweb: There can be empty patches (in git_patchset_body)

gitweb: There can be empty patches (in git_patchset_body)

We now do not skip over empty patches in git_patchset_body
(where empty means that they consist only of git diff header,
and of extended diff header), so uncomment branch of code dealing
with empty patches (patches which do not have even two-line
from/to header)

Signed-off-by: Jakub Narebski <jnareb@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>