use AUTHSNMP_ID to get the proper credentials

Reported-by: Tomás Abad <tabadgp@gmail.com>
more complete fix for previous issue

This version also fix model transmission to _queryDevice() method, and
is closer from 2.3.0 code.
pass logger to setConnectedDevicesMacAddresses()
fix missing documentation
kill spurious whitespace
no need for undefined values
but we need 0 values
no need for undefined ports list
initial import
fix expected results
new tests
new tests
use logger instead of calling warn()
use logger only if available
more tests
no need for debug output
don't report empty hostnames
no need for empty ports list
no need for undefined values
use getCanonicalMacAdddress() everywhere

where mac adresse are involved.