This patch fixes some inconsistencies betwen the network
design doc and the actual user interface. Adding reserved
ips works with option --add-reserved-ips and removing them
with --remove-reserved-ips. There is no toggling of the
reservation status of ips.

Signed-off-by: Helga Velroyen <helgav@google.com>
Reviewed-by: Guido Trotter <ultrotter@google.com>