fixed key error when dlist empty
fixed key error when dlist empty

api_1           |   File "/opt/jenova/resources/distribution_list.py",
line 179, in get
api_1           |     for accounts in
r['GetDistributionListResponse']['dl']['dlm']:
api_1           | KeyError: 'dlm'

inova-tecnologias/jenova,inova-tecnologias/jenova