dhclient.conf should request nis-domain etc. by default

I filed a bug against the "nis" package that they don't provide any dhclient-exit-hooks.d hook scripts to handle nis-domain/nis-servers/nisplus-domain/nisplus-servers DHCP options: https://bugs.launchpad.net/bugs/246322

I also suggested that they need to modify the dhclient.conf script when nis is installed, so that it adds these options to the "request" field otherwise those values won't be obtained anyway. However, thinking about it now I wonder if it's even possible for another package to update dhclient.conf, given the Debian/Ubuntu packaging rules.

So, I'm filing this bug asking that these four options be included in the "request" field by default in the dhclient.conf file provided by dhcp3-client, so that when the "nis" package provides the proper hook scripts they will actually be used.

For reference there's a similar request for the ntp-servers DHCP option here: https://bugs.launchpad.net/bugs/74164