CURLOPT_CRLF(3) on macOS

The text ac829243a519, 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.

enable/disable CRLF conversion

CURLOPT_CRLF(3) on macOS now