start_nameserver.sh "nameserver up" detection fix (at least on Ubuntu Precise LTS)

Nameserver would come up but script's detection relied on it a mechanism to detect which wasn't reliable on Ubuntu Precise LTS. This might break other platforms, I don't know. This fix made it work in my environment (vanilla Ubuntu Precise LTS + latest docker on said Ubuntu via vagrant on Mac OS).    

 # Note: original scripts assumed the nameserver resolves its own hostname to 127.0.0.1
    # bmustafa (24601 on GitHub) has found this not to necessarily be the case 
    # on Ubuntu Precise LTS...this fixes it...may break other platforms? 

see comments.