iSCSI and RBD volumes don't work as Kubernetes services - these protocols
are broken by S-NAT created by kube-proxy - at least iSCSI exhanges real
IP address of the iSCSI target as part of the protocol.
This reverts commit 118004c166.
This helps with routing of TCP traffic between clients and servers in case
flannel or similar service is not installed and pods don't see each other.
- It needs 'insecure' in /etc/exports to allow NFS clients on ports > 1024,
Kubernetes service will change client port to a random number.
- glusterfs no longer needs explicit endpoint definition, it uses the service
instead.
