As per ECR 1416 change in UEFI Shell Specification 2.2,
enhancing 'cls' command to change the background color as well as
foreground color. Also add support to display current settings
using 'cls -sfo' command.
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Tapan Shah <tapandshah@hpe.com>
Reviewed-by: Jaben Carsey <jaben.carsey@intel.com>