Split a string containing whitespace or comma separated host or
IP addresses and port numbers of the form "host:port host2:port"
or "host:port, host2:port" into a List of InetSocketAddress
instances suitable for instantiating a MemcachedClient.
Creates a cluster aware TapClient
This type of TapClient will TAP all servers in the specified cluster and
will react to changes in the number of cluster nodes.