Dashboard: Fixed logout ajax problem.

Signed-off-by: matematik7 <domen.ipavec@z-v.si>
Dashboard: Made background updating reusable.

Signed-off-by: matematik7 <domen.ipavec@z-v.si>
Dashboard: Implemented cpu page for dashboard.

Signed-off-by: matematik7 <domen.ipavec@z-v.si>