tests/test-serve.out

Document log date ranges and mention 'hg help dates' for all commands (issue998)

% Without -v
access log created - .hg/hgrc respected
% With -v
listening at http://localhost/
% With --prefix foo
listening at http://localhost/foo/
% With --prefix /foo
listening at http://localhost/foo/
% With --prefix foo/
listening at http://localhost/foo/
% With --prefix /foo/
listening at http://localhost/foo/