revamp resolvconf

  * always remove cloudstack nameserver
  * add platform-services nameservers with highest priority
  * add optional fallback_nameservers with lowest priority
enable parametization of forwarders and recursion for platform_services_dns::server
Merge branch 'feature/resolving-revamped' into development
puppetmaster: add fqdn and front_fqdn for ssl dns_alt_names
platform_services_authconfig: add CAcert for ldap.swisstxt.ch