GraphicsMagick initialisation and localisation

[Søren Hauberg]

Hi All

For long we have had the issue the in certain versions of GraphicsMagick
the localisation is changed when GraphicsMagick is initialised. This
effectively, meant that all date functions failed after an image was
read or written from Octave.

I have checked in the following changeset for this issue (it simply
restores the locale after the GraphicsMagick initialisation):

  http://hg.savannah.gnu.org/hgweb/octave/rev/d27bd2f74137

I could not find a bug report on the issue, so I'm just notifying you
guys on this list instead.

Soren