Documented --dns-* options in curl manpage

Disabling EPSV only changes the passive behavior. If you want to switch to

active mode you need to use \fI-P, --ftp-port\fP.

.IP "--dns-interface <interface>"

Tell curl to send outgoing DNS requests through <interface>. This option

is a counterpart to \fI--interface\fP (which does not affect DNS). The

supplied string must be an interface name (not an address).

This option requires that libcurl was built with a resolver backend that

supports this operation. The c-ares backend is the only such one. (Added in

7.33.0)

.IP "--dns-ipv4-addr <ip-address>"

Tell curl to bind to <ip-address> when making IPv4 DNS requests, so that

the DNS requests originate from this address. The argument should be a

single IPv4 address.

This option requires that libcurl was built with a resolver backend that

supports this operation. The c-ares backend is the only such one.  (Added in

7.33.0)

.IP "--dns-ipv6-addr <ip-address>"

Tell curl to bind to <ip-address> when making IPv6 DNS requests, so that

the DNS requests originate from this address. The argument should be a

single IPv6 address.

This option requires that libcurl was built with a resolver backend that

supports this operation. The c-ares backend is the only such one.  (Added in

7.33.0)

.IP "--dns-servers <ip-address,ip-address>"

Set the list of DNS servers to be used instead of the system default.

The list of IP addresses should be separated with commas. Port numbers

may also optionally be given as \fI:<port-number>\fP after each IP

address.

This option requires that libcurl was built with a resolver backend that

supports this operation. The c-ares backend is the only such one.  (Added in

7.33.0)

.IP "-e, --referer <URL>"

(HTTP) Sends the "Referer Page" information to the HTTP server. This can also

be set with the \fI-H, --header\fP flag of course.  When used with