basic listipdus command, xpath works nice here

~/src/git/acs6000/src (develop) 11-$ ./pmCommand.py -v
DEBUG: Using pmCommand version UNRELEASED
(Cmd) login admin 1
DEBUG: Login successful, got sid: c0c7e6a5577de06f72f60e27cece907a
(Cmd) listipdus
['power3', 'power5', 'power2', 'power4', 'power6']
(Cmd)