CURLOPT_CRLF(3) on macOS

The text 0c8ed74a4f18, as OS X 10.11.6, OS X 10.11.5, OS X 10.11.4, OS X 10.11.3, OS X 10.11.2, OS X 10.11.1, OS X 10.11, OS X 10.10.5 shipped it.

enable/disable CRLF conversion

CURLOPT_CRLF(3) on macOS now