TODO: c-ares and CURLOPT_OPENSOCKETFUNCTION

 1.10 auto-detect proxy

 1.11 minimize dependencies with dynamically loaded modules

 1.12 updated DNS server while running

 1.13 DNS-over-HTTPS

 1.13 c-ares and CURLOPT_OPENSOCKETFUNCTION

 1.14 Typesafe curl_easy_setopt()

 1.15 Monitor connections in the connection pool

 1.16 Try to URL encode given URL

 https://github.com/curl/curl/issues/2251

1.13 DNS-over-HTTPS

1.13 c-ares and CURLOPT_OPENSOCKETFUNCTION

 By adding support for DNS-over-HTTPS curl could resolve host names using a

 totally separate name server than the standard system resolver, while at the

 same time doing so over a communication channel that enhances privacy and

 security.

 curl will create most sockets via the CURLOPT_OPENSOCKETFUNCTION callback and

 close them with the CURLOPT_CLOSESOCKETFUNCTION callback. However, c-ares

 does not use those functions and instead opens and closes the sockets

 itself. This means that when curl passes the c-ares socket to the

 CURLMOPT_SOCKETFUNCTION it isn't owned by the application like other sockets.

 https://github.com/curl/curl/wiki/DNS-over-HTTPS

 See https://github.com/curl/curl/issues/2734

1.14 Typesafe curl_easy_setopt()