- Add curl as BuildRequires/Requires to be able to use the '-curl'
option (eg. in DDCLIENT_OPTIONS in /etc/sysconfig/ddclient).

- Update to 3.10.0:
* Added support for domaindiscount24.com
* Added support for njal.la
* Added support for Cloudflare API tokens
* Added support for OVH DynHost.
* Added support for ClouDNS.
* Added support for dinahosting.
* Added support for Gandi LiveDNS.
* The freedns protocol (for https://freedns.afraid.org) now supports IPv6
addresses.
* New ssl_ca_dir and ssl_ca_file options to specify the location of CA
certificates.
* New built-in IP discovery service shorthands:
+ googledomains from https://domains.google
+ he from https://he.net
ip+4only.me, ip6only.me from http://whatismyv6.com
+ ipify-ipv4 and ipify-ipv6 from https://www.ipify.org
+ myonlineportal from https://myonlineportal.net
+ noip-ipv4 and noip-ipv6 from https://www.noip.com
+ nsupdate.info-ipv4 and nsupdate.info-ipv6 from
+ https://www.nsupdate.info
+ zoneedit from https://www.zoneedit.com
* Added option -curl to access network with system Curl command instead
of the Perl built-in IO::Socket classes.
* Added option -{no}web-ssl-validate and -{no}fw-ssl-validateto provide
option to disable SSL certificate validation. Note that these only apply for
network access when obtaining an IP address with use=web or use=fw