Merge branch 'stable-3.1' into 'stable-3.1'

interface/lib/app.inc.php

interface/lib/classes/db_mysql.inc.php

interface/lib/classes/ids.inc.php

interface/lib/classes/plugin_listview.inc.php

interface/lib/classes/tform.inc.php

interface/lib/classes/tform_actions.inc.php

interface/lib/classes/tform_base.inc.php

interface/lib/classes/tpl.inc.php

interface/web/admin/directive_snippets_edit.php

interface/web/admin/firewall_edit.php

interface/web/admin/server_edit.php

interface/web/admin/server_ip_map_edit.php

interface/web/client/client_del.php

interface/web/client/client_message.php

interface/web/client/message_template_edit.php

interface/web/dns/dns_dkim_edit.php

interface/web/dns/dns_dmarc_edit.php

interface/web/dns/dns_import.php

interface/web/dns/dns_slave_edit.php

interface/web/dns/dns_soa_edit.php