Merged revisions 4069-4117 from stable branch.

install/dist/lib/fedora.lib.php

install/dist/lib/opensuse.lib.php

install/install.php

install/lib/installer_base.lib.php

install/lib/mysql.lib.php

install/sql/incremental/upd_0055.sql

install/sql/incremental/upd_0056.sql

install/sql/ispconfig3.sql

install/tpl/config.inc.php.master

install/tpl/system.ini.master

interface/lib/classes/aps_guicontroller.inc.php

interface/lib/classes/client_templates.inc.php

interface/lib/classes/listform.inc.php

interface/lib/classes/plugin_backuplist.inc.php

interface/lib/classes/remoting.inc.php

interface/lib/classes/remoting_lib.inc.php

interface/lib/classes/tform.inc.php

interface/lib/classes/tree.inc.php

interface/lib/lang/ar.lng

interface/lib/lang/bg.lng