updated nokia parsing and tests

inventory_provider/nokia.py

inventory_provider/tasks/worker.py

test/data/nokia/rt0.ams.nl.geant.net-netconf.xml

test/data/nokia/rt0.fra.de.geant.net-netconf.xml

test/data/nokia/rt0.gen.ch.geant.net-netconf.xml

test/data/nokia/rt0.lon.uk.geant.net-netconf.xml

...a/rt0.lon.uk.lab.office.geant.net-netconf-nokia-state.xml

...a/nokia/rt0.lon.uk.lab.office.geant.net-netconf-nokia.xml

test/data/nokia/rt0.lon2.uk.geant.net-netconf.xml

test/test_nokia.py

test/test_nokia_data_tmp.py

test/test_worker.py