[GH-521] - undefined method for 'ipv4_address'
[GH-521] - undefined method for 'ipv4_address'

* Fixes ipv4_address on line 45
* Logic to properly handle null port_name property found after fixing ipv4_address

Signed-off-by: Jeff Mery <898aa9f1d1268fe10c9934950f8a534405ca308d@chef.io>

rlaveycal/windows,chef-cookbooks/windows,opscode-cookbooks/windows,daptiv/windows