Issue 498/support auto proxy connector http+https+socks5+socks5h

[soundofspace]

• Adds socks5(h) support to EasyWebClient
  • Add proxy connector that supports both http and socks5 proxies and delegates to a specific connector depending on proxy protocol
  • Kept this connector specific (read: not generic) to our HttpProxyConnector/Socks5ProxyConnector since this is used for EasyWebClientBuilder specifically and saw no real value in making this generic. For special use cases we already support bringing a custom proxy connector
  • Another option was also. Currently you can configure existing ProxyConnectors in optional mode which forwards traffic to inner one if proxy is not configured. I could have modified this to also forward traffic to inner svc if Proxy protocol was wrong instead of returning error like we do now, but this felt ugly and error prone in the long run
  • Right now I focussed on http(s) + socks5(h) only, not a generic amount of proxy connectors. Once we add one more I have some "scalable" ideas for this but didn't want to overcomplicate the current setup for something we might not support for quite some time
• Move EasyWebClient to rama crate as now its not specific to http anymore
• Move autobahn example to rama examples so it can use EasyWebClient

[GlenDC]

Looks good. Only have some minor / nitpick comments. I would still like these to be resolved, but the work is excellent. Thanks a lot! Wonderful addition.

Only thing I see missing here that I would have still expected to be in scope for this PR is that you did not remove yet the manual clients in socks5 tests where now you can just use the regular runner client that is part of the example utils. Right?

[GlenDC]

LGTM, couple of last remarks but these are details that you can probably resolve without any controversy and merge it yourself afterwards if you have the confidence.