message: add some more examples

to at least show it can take and substitute
translated format strings

Change-Id: Ibd8384655986b266c0f1355537d61c06d0663474
Reviewed-on: https://go-review.googlesource.com/60772
Run-TryBot: Marcel van Lohuizen <mpvl@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Nigel Tao <nigeltao@golang.org>