This reverts commit f8ce5996b0.
etcd no longer resolves TCP addresses passed in through flags,
so there is no need to compare hostname and IP slices anymore.
(for more details: a3892221ee)
Conflicts:
etcdserver/cluster.go
etcdserver/config.go
pkg/netutil/netutil.go
pkg/netutil/netutil_test.go
pkg/ is a collection of utility packages used by etcd without being specific to etcd itself. A package belongs here
only if it could possibly be moved out into its own repository in the future.
3153e635d5