feat: support ToS routing rule

[mzz2017]

Out-of-date

Please see #294 for the final version!

Background

Support tos routing rule.

According to http://libtorrent.org/reference-Settings.html#peer_tos, the default value of dscp and tos is 0x04 in libtorrent.

This PR gives a BitTorrent bypass method.

Example:

routing {
  // decimal
  tos(50) -> direct
  // hex
  tos(0x4) -> direct
}

Also see #295.

Checklist

• The Pull Request has been fully tested
• There's an entry in the CHANGELOGS
• There is a user-facing docs PR against https://github.com/daeuniverse/dae

Full Changelogs

• [Implement ...]

Issue Reference

Closes #[issue number]

Test Result

[mzz2017]

Test result:

[dae-prow]

🧪 Since the PR has been fully tested, please consider merging it.