Merge remote branch 'upstream/develop' into develop

include/class.file.php

include/class.format.php

include/class.forms.php

include/class.mailfetch.php

include/class.orm.php

include/class.upgrader.php

include/client/header.inc.php

include/staff/header.inc.php

include/staff/login.header.php

include/staff/system.inc.php

include/staff/templates/task-view.tmpl.php

include/staff/templates/users.tmpl.php

setup/inc/header.inc.php