add --force alias for --no-shortcut option to list-changes

I can never remember what the option --no-shortcut is called, so add
aliases --force and -f which are the more common name for this sort of
option.

Change-Id: I466a04e58c84c07d2f43352913e540b8e6d3bbf2
Signed-off-by: Doug Hellmann <doug@doughellmann.com>

openstack_releases/cmds/list_changes.py

@@ -204,7 +204,7 @@ def main():
         help='do not remove temporary files',
     )
     parser.add_argument(
-        '--no-shortcut',
+        '--no-shortcut', '--force', '-f',
         dest='shortcut',
         default=True,
         action='store_false',