More string changes in the control-centre

[Jody Goldberg <jody gnome org>]

http://bugzilla.gnome.org/show_bug.cgi?id=134446

There were two minor spacing changes in the control center that I
just patched.  To avoid trouble I updated all the translations to
correspond to the change.  However, as noted in the report, fixing
the problem turned up a missing string that needs to be translated.

Apologies
    Jody