Merge remote-tracking branch 'sebj/master' and tidied up merged code

Conflicts:
	interface/lib/classes/custom_datasource.inc.php
	interface/lib/classes/validate_client.inc.php
	interface/web/client/client_edit.php
	interface/web/dns/dns_soa_edit.php
	interface/web/dns/dns_wizard.php
	interface/web/mail/mail_domain_edit.php
	interface/web/sites/database_edit.php
	interface/web/sites/web_domain_edit.php