- further XSS fixes for #4902 (reflected XSS)

interface/lib/app.inc.php

interface/lib/classes/plugin_listview.inc.php

interface/web/client/client_message.php

interface/web/dns/dns_wizard.php

interface/web/index.php

interface/web/login/index.php

interface/web/login/password_reset.php

interface/web/sites/web_childdomain_list.php

interface/web/sites/web_vhost_domain_list.php

interface/web/tools/dns_import_tupa.php

interface/web/tools/import_ispconfig.php

interface/web/tools/import_vpopmail.php