Qt5 QInputMethod

Hi Christian,

while working with the QtVirtualKeyboard, I noticed that I can attach a QInputMethod directly to the keyboard which is a much cleaner solution than using a hidden input field.

As far as I understood it, it is required to create a custom implementation of QInput(Method|Engine|Context) (like it is done in qtbase/src/plugins/plastforms). What do you think is the best approach to implement this part? I though about either doing it directly in the keyboard application (which might be more portable) or adding it to the nitpicker integration in /qt5/qtbase/src/plugins/platforms/nitpicker (which would make it accessible for more applications).

Regards, Johannes