gnome-control-center: UI Freeze Break request (Bug 706239)

[Ondrej Holy <oholy redhat com>]

It would be nice to land this:

Bug 706239 - Background in login history is different from all other lists
https://bugzilla.gnome.org/show_bug.cgi?id=706239
(screenshot: https://bug706239.bugzilla-attachments.gnome.org/attachment.cgi?id=254567)

This patch slightly change UI of the history dialog in the User Accounts panel. It ports history dialog to 
use GtkListBox instead of GtkGrid to be more consistent with other panels. It changes background color to 
white as was designed before (it has been changed with gnome themes changes before while). 

The patches is reviewed and accepted to commit now by Rui Matos and approved by Andreas Nilsson.

Regards

Ondrej Holy