effects/slide: Allow overshooting when desktop wrapping is disabled

Vlad Zahorodniirequested to merge
work/zzag/effects-slide-allow-overshoot into master

It's a nice visual touch. It gives user feedback - kwin handles the gesture but there's no desktop to left or right, etc.

Given that animations are driven by a TimeLine, this change makes the slide effect use a QEasingCurve instead of using a physics based spring model.

Merge request reports