Extract function to parse args into outlets

Also, error when no args given:

(Cmd) on
ERROR: No outlet specified.

JFF:

(Cmd) lock sdf
ERROR: Invalid outlet: sdf
(Cmd) lock sdf[6]
ERROR: The appliance configuration has been altered from outside of your
session.
ERROR: Outlet sdf[6] not found.
(Cmd) on power2[1], power2[3]
ERROR: Action error: outlet locked. Action: ON. Outlet(s): power2[1].
INFO: power2[1]: status of outlet hpswitch is now: OFF(locked)
ERROR: Action error: outlet locked. Action: ON. Outlet(s): power2[3].
INFO: power2[3]: status of outlet 20-ba-aeP0_1 is now: ON(locked)
(Cmd) unlock power2[1], power2[3]
INFO: power2[1]: status of outlet hpswitch is now: OFF
INFO: power2[3]: status of outlet 20-ba-aeP0_1 is now: ON