When git checkout -p from the index or HEAD is run in edit mode, the
help message about removing '-' and '+' lines was backwards. Because it
is reverse applying the patch, the meanings of '-' and '+' are reversed.
Signed-off-by: Jonathan "Duke" Leto <jonathan@leto.net> Acked-by: Thomas Rast <trast@student.ethz.ch> Signed-off-by: Junio C Hamano <gitster@pobox.com>