[WIP] Add proxy and onion support for ckb-network

[eval-exec]

What problem does this PR solve?

Add network.proxy and network.onion config:

# [network.proxy]
# proxy_url = "socks5://127.0.0.1:7891"

# [network.onion]
# listen_on_onion = false
# onion_service_target = "127.0.0.1:8115"
# onion_server = "127.0.0.1:9050"
# tor_controller = "127.0.0.1:9051"
# tor_password = ""

Then, start a tor server: tor --SocksPort 9050 --ControlPort 9051, finaly, start the ckb node, if network.onion.listen_on_onion is true, it will auto connect to the tor server, and use tor control port to create onion service.

Related changes

• Add ProxyConfig and OnionConfig to network config
• Support socks5 authentication like: socks5://<username>:<password>@server_host:port
• Support connect to onion ckb node, and listen on the onion hidden network
• [WIP] Integration test for ckb-onion
  • node1(onion) can succesfully connect node2(node2) in the onion network
  • noode1(onion) can succesfully connect to node2(non-onion)
  • node1(onion) connect node0(onion), node2(onion) connect to node0, expect node1 and node2 can reach each other
  • node1(non-onion) can use [network.proxy] via a normal socks5 proxy
• ckb-onion related configuration's documentation in ckb.toml

Note:
Need to setup promethues for tor process: https://gitlab.torproject.org/tpo/onion-services/onionprobe

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code ci-runs-only: [ quick_checks,linters ]

Side effects

• None

Release note

Title Only: Include only the PR title in the release note.

[eval-exec]

nervosnetwork/tentacle#392