Preferences Scroll Speed is too fine-grained

[HackBrettHB]

In my opinion, every double with 2 digits after the decimal between 1.0 and 16.0 is way too fine-grained.
We should reduce this to clip at for example every .25 or reduce the granularity to 1 digit after the decimal.
Additionally: The lower limit currently is 1.1 -> I think 1.0 is more reasonable

I will open a pull request for this.