Hitting Ctrl-D (EOF) is a common way to exit shell-like tools.
When in a sub-menu it will still behave as if an empty line had
been entered, carrying out the action on the selected items and
returning to the previous menu.
Signed-off-by: Jean-Luc Herren <jlh@gmx.ch> Signed-off-by: Junio C Hamano <gitster@pobox.com>