Create a swarm bootnode

[nonsense]

At the moment both p2p package and Swarm hive protocol handle node discovery and connections to peers, which is problematic for a number of reasons.

We want to configure the p2p package to not connect to any random nodes, and handle connections to new peers from the Swarm Kademlia implementation and SuggestPeer functionality.

For this purpose we need to create a Swarm bootnode, which runs the hive protocol, so that Swarm Kademlia implementation can take of new connections to nodes.

At the moment the bootnode cmd does not run hive, so if we turn off random peer dialling in the p2p package, we end up with 0 peers in all Swarm nodes. However if random peer dialing is on we end up with full connectivity #1094

[nonsense]

In progress at:
#1138
ethersphere/helm-charts#32

[skylenet]

Prod bootnode setup: https://github.com/ethereum/swarm-cluster/pull/121