Fix return codes, if ip data at Godaddy.com and Cloudflare.com are
already up to date, handle it as succesful update.

Signed-off-by: Christian Schoenebeck <christian.schoenebeck@gmail.com>

- update_cloudflare_com_v4.sh: enclose urls in single quotes
- dynamic_dns_functions.sh: force to return only one ip, if using nslookup to get registered ip

Signed-off-by: Christian Schoenebeck <christian.schoenebeck@gmail.com>

- tld_names.dat.gz
  - rename to public_suffix_list.dat.gz
  - (re)created during build
  - new location /usr/share
- move services files to /etc/ddns
- new services
  - CloudFlare.com-v4 using API-Version 4 without using public_suffix_list.dat
  - GoDaddy.com
  - both depending on cURL package
  - both with modified syntax for option domain ( NEW: [host[.subdom]@]domain.tld )
- new service
  - Now-DNS.com formerly Now-IP.com
- service afraid.org now supports key-auth and basic-auth
- new command line options for dynamic_dns_updater.sh and dynamic_dns_updater.sh
- adapted ddns.init and ddns.hotplug to new command line options
- renaming config options inside section global

Signed-off-by: Christian Schoenebeck <christian.schoenebeck@gmail.com>