fuzzy/cluster.go
func containsNode(nodes []*raftNode, n *raftNode) bool {
	for _, rn := range nodes {
		if rn == n {
			return true
		}
	}
	return false
}
func containsNode(nodes []*raftNode, n *raftNode) bool {
	for _, rn := range nodes {
		if rn == n {
			return true
		}
	}
	return false
}
// containsNode returns true if the slice 'nodes' contains 'n'