Password required to load the private key in B<ClientKey>.
+=item B<Header> I<Header>
+
+A HTTP header to add to the request. Multiple headers are added if this option is specified more than once. Example:
+
+ Header "X-Custom-Header: custom_value"
+
=item B<SSLVersion> B<SSLv2>|B<SSLv3>|B<TLSv1>|B<TLSv1_0>|B<TLSv1_1>|B<TLSv1_2>
Define which SSL protocol version must be used. By default C<libcurl> will