[PATCH] test: use (format "%S") to print nil in emacs test.

[David Bremner]

david at tethera.net writes:

> From: David Bremner <bremner at debian.org>
>
> The behaviour of "emacsclient --eval nil" changed from emacs23 to
> emacs24, and in emacs24 it prints 'nil' rather than an empty string.

pushed, 

d