Small patch to fix typo and get rid of gcc warning

[John W. Eaton]

On  2-Feb-2008, Shai Ayal wrote:

| 2008-02-02  Shai Ayal  <shaiay at users.sourceforge.org>
| 
|         * graphics.h.in (class base_scaler): added virtual destructor
|         * graphics.cc (properties::update_camera): fixed typo

I applied this patch and checked it in.

Thanks,

jwe