merge master into single-user-mode

apps/files/js/filelist.js

apps/files_external/lib/dropbox.php

apps/files_external/lib/swift.php

apps/files_external/lib/webdav.php

apps/files_trashbin/ajax/delete.php

apps/files_trashbin/js/filelist.js

apps/files_trashbin/js/trash.js

apps/files_trashbin/templates/index.php

core/command/app/disable.php

core/command/app/enable.php

core/command/app/listapps.php

core/css/styles.css

core/register_command.php

lib/base.php

lib/private/connector/sabre/filesplugin.php

lib/private/defaults.php

lib/private/request.php

lib/public/activity/iconsumer.php

lib/public/activity/imanager.php

lib/public/appframework/app.php