[QT*] unpredictive keyboard

[Roland]

Hello Leonardo and Franky,

I haven't tried out your changes yet but they sound very useful. I would
also prefer the three switching buttons suggested by Franky. I think when
putting them e.g. at the far right, they wouldn't really fill up the space
too much or make the other keys too small.

Another idea: Wouldn't it be possible to toggle the predictability of the
keyboard through an option in the context (options) menu? By putting a
checkmark in front you would also have a visual information about the state.
I think this should be possible because when changing to the undocked
keyboard the option "Change input Method" changes into a submenu.

Roland