CURLOPT_CRLF(3) on macOS

The text bbc28118f8df, as OS X 10.10.4, OS X 10.10.3, OS X 10.10.2, OS X 10.10.1, OS X 10.10 shipped it.

enable/disable CRLF conversion

CURLOPT_CRLF(3) on macOS now