UDP trackers

[vimpunk]

It's a fairly easy win yet it's a very useful feature as most trackers nowadays communicate over UDP rather than HTTP.

[hedonhermdev]

Hey, if you would like me to work on this issue I can. I have some experience with the Bittorrent protocol from the one I was writing in GoLang.

[vimpunk]

Hey @hedonhermdev, contributions are very much welcome, feel free to give it a shot!

[billyb2]

@mandreyel , I've started to work on adding UDP trackers! My current work is here. If you'd give some criticism of how it looks so far, that would be great! If not, that's totally alright, but I'm hoping I can send a pull request.

[vbakc]

@billyb2 can you open pull request, please? Or a draft pull request, if it's not done yet.
To me, it's better to use struct instead of tuple in metainfo.rs:84

[billyb2]

@vbakc sure! I added it here

[vbakc]

@billyb2 thank you) Added comment about what I talked about.
@mandreyel can you share, what do you think about it?