Merge branch 'florian030/ispconfig3-master' into stable-3.1

interface/web/mail/xmpp_domain_edit.php

interface/web/sites/database_quota_stats.php

interface/web/sites/web_vhost_domain_edit.php

interface/web/tools/lib/lang/ar_usersettings.lng

interface/web/tools/lib/lang/bg_usersettings.lng

interface/web/tools/lib/lang/br_usersettings.lng

interface/web/tools/lib/lang/ca_usersettings.lng

interface/web/tools/lib/lang/cz_usersettings.lng

interface/web/tools/lib/lang/de_usersettings.lng

interface/web/tools/lib/lang/el_usersettings.lng

interface/web/tools/lib/lang/en_usersettings.lng

interface/web/tools/lib/lang/es_usersettings.lng

interface/web/tools/lib/lang/fi_usersettings.lng

interface/web/tools/lib/lang/fr_usersettings.lng

interface/web/tools/lib/lang/hr_usersettings.lng

interface/web/tools/lib/lang/hu_usersettings.lng

interface/web/tools/lib/lang/id_usersettings.lng

interface/web/tools/lib/lang/it_usersettings.lng

interface/web/tools/lib/lang/ja_usersettings.lng

interface/web/tools/lib/lang/nl_usersettings.lng