Added name server facts to the setup module.

Added three new facts to the setup module:

*  all_nameservers: A list of IP addresses of all configured name servers.
*  default_nameserver: The first IP address in all_nameservers.
*  resolv_domain: The value of the 'domain' entry used for searching non-dot terminated domains.

All data is taken from /etc/resolv.conf using http://pic.dhe.ibm.com/infocenter/aix/v6r1/index.jsp?topic=%2Fcom.ibm.aix.files%2Fdoc%2Faixfiles%2Fresolv.conf.htm as a file format reference.