CURLOPT_PROXYTYPE(3) on macOS

The text 2c93062b9263, as macOS 10.12.5, macOS 10.12.4, macOS 10.12.3, macOS 10.12.2, macOS 10.12.1, macOS 10.12 shipped it.

proxy protocol type

CURLOPT_PROXYTYPE(3) on macOS now