add_dns

Description:

public bool add_dns (string dns)

Adds a new DNS server to the setting.

Parameters:

this	the SettingIPConfig
dns	the IP address of the DNS server to add

Returns:

true if the DNS server was added; false if the server was already known

Before 1.42, setting dns to an invalid string was treated as user-error. Now, also invalid DNS values can be set, but will be rejected later during verify.