proxy: allow use of at char in passwords
proxy: allow use of at char in passwords

Applies to both http proxy and socks proxy

https://github.com/warmcat/libwebsockets/issues/1247
sartura/libwebsockets,sartura/libwebsockets,sartura/libwebsockets,sartura/libwebsockets,sartura/libwebsockets,sartura/libwebsockets,sartura/libwebsockets