make ASN compatible with node 0.11
added check for DNS results
update two remaining tests with 'fix'
asn: test obj before accessing it
empty ASN results are now null/undefined (was '')
asn: log some more debugging
asn: use JS syntax for join
asn: replace a for loop with async.each and

dns_results now returns an error as the first result param
Merge pull request #751 from msimerson/asn

Asn