Add option to close Kate when last file closes
Summary: This is a proposal for Kate following the discussion in D15278.
Open one file in Kate.
In Settings > General options, enable the new option "Close Kate entirely when the last file is closed"
Close the file by any mean (tab button, Ctrl-W, ...)
Kate should shutdown.
Reviewed By: Kate, cullmann
Subscribers: filipesaraiva, pino, aacid, cullmann, zetazeta, ngraham, kwrite-devel
Differential Revision: https://phabricator.kde.org/D16169