Feature(s) request

[tim-gromeyer]

First of all, it works perfectly and I'm very happy with it. I would also like to be able to check if undo and redo are avaiable via isUndoAvaiable() and isRedoAvaiable(). I also noticed that with older Qt versions < 5.15 an error occurs when running cmake:

CMake Error at CMakeLists.txt:65 (QT_ADD_TRANSLATION):
  Unknown CMake command "QT_ADD_TRANSLATION".

After changing it to

IF(NOT Qt6_FOUND)
QT5_ADD_TRANSLATION(qtspell_QM ${qtspell_TS})
ELSE(NOT Qt6_FOUND)
QT6_ADD_TRANSLATION(qtspell_QM ${qtspell_TS})
ENDIF(NOT Qt6_FOUND)

it worked again. I would be very grateful if you could change that. Nevertheless, thank you in advance.