Proxy support

[Crystal-RainSlide]

Would be helpful to connection problems.

If this requires some extended time to develop, change the program to follow system proxy by default can be a start.

To everyone who is facing connection problems and want to use proxy: proxychains-windows is not working perfectly by default, since F95Checker need to start a RPC server to connect with its browser extension.

Error message when using proxychains-windows for proxy:

Failed to start RPC server on localhost port xxxxx:
OSError: [winError10049]

This means that the web browser extension will not work, while F95Checker
itself should be unaffected. Some common causes are:
- Hyper-V
- Docker
- -Antivirus or firewall