Implement whitebind/whitelist for inbound peers

[pinheadmz]

From Bitcoin Core docs:

-whitebind=<addr>, Bind to given address and whitelist peers connecting to it.
Use [host]:port notation for IPv6

-whitelist=<IP address or network>,  Whitelist peers connecting from the given IP
address (e.g. 1.2.3.4) or CIDR notated network (e.g. 1.2.3.0/24).
Can be specified multiple times. Whitelisted peers cannot be DoS banned

These options will make it very easy to tether a user's light client to their own personal full node.

[braydonf]

The necessary feature here of having one port for inbound peers and another port for outbound peers, will furthermore resolve having the host of a node be a Tor onion address at the same time as connecting to outgoing nodes over Tor, as describe in https://github.com/bcoin-org/bcoin/issues/206.

An onion address will also help the use case of connecting a light client to a personal or trusted node. As there are not issues with:

• Non-static and rotating IP addresses.
• TLS certificates signed by a CA, or configuration of self-signed CA on devices.
• Configuration of router to forward ports and configuration of firewalls.
• Cleartext protocol messages (for .onion addresses).

[hublex]

any ideas what I need to change? In the node settings I didn't find anything about whitlist or whitebind.