BIND does not need a root hints file

I just noticed that the root hints file distributed in the bind formula was out of date. It had the wrong IPv4 address of d.root-servers.net, and was missing the IPv6 address of c.root-servers.net. I first thought about updating it, but then decided to remove it altogether. This is because the bind source ships with a root hints file, and this file is built into the named binary. Therefore, when named starts, if there is no root hints file configured in named.conf, it uses the built-in list to do a priming query. This is a better approach, because we can rely upon ISC maintaining an up-to-date root hints file with every new release of BIND.

To support my pull request, I also refer to the following bug report in Fedora:

https://bugzilla.redhat.com/show_bug.cgi?id=901741#c4

Additionally, the same point is made in this post on the bind-users mailing list:

http://lists.centos.org/pipermail/centos/2013-February/132354.html