Expose reuse_port option for TCP and WebSocket transports

[dmitry-markin]

Add reuse_port option to TCP & WebSocket configs. When set, this both:

1. Sets SO_REUSEPORT on sockets.
2. Binds sockets to the listen address port when making outbound connections.

I'm not sure if these two behaviors should be controlled by a single option, but this follows libp2p convention.

CC @altonen

[dmitry-markin]

While at this PR I noticed that our rustfmt.toml doesn't include match_block_trailing_comma = true, which is present in poladot-sdk rustfmt.toml. I'm going to add it and reformat the repo in a follow-up PR if you don't mind @altonen @lexnv