support multiple tcp tunnels and multiple udp tunnels in rstunc

[aa51513]

★support multiple tcp tunnels and multiple udp tunnels in rstunc via multiple quic channels

command example:

rstunc
  --mode OUT \
  --server-addr 1.2.3.4:6060 \
  --password 123456 \
  --cert path/to/cert.der \
  --tcp-mapping IN^0.0.0.0:2900^2800,OUT^0.0.0.0:4900^4800,0.0.0.0:6900^6800 \
  --udp-mapping IN^0.0.0.0:1900^1800,OUT^0.0.0.0:3900^3800,0.0.0.0:5900^5800 \
  --loglevel D

special note: For compatibility reasons, I do not deleted the parameter of mode to ensure that the original command can be executed successfully.

[aa51513]

Maybe you can see that I am a Rust beginner and made many low-level mistakes in the process of modifying the code. Fortunately, you have the patience to point out

[neevek]

I've been really busy lately, but I'll review your code as soon as I have some free time. In the meantime, you can continue to refine your implementation or do more tests, and at the end squash all the commits into one.

[aa51513]

Apologies for the late reply – been buried in work and haven't touched my code since. Still crazy busy to be honest