Revert "Upgrade the default scroll distance to 120"
This was part of the high-resolution wheel work that was factored out ahead of time. Problem is: this breaks scroll button emulation in the server as we use the distance to determine when we click buttons 4-7.
Before: movement of 15 normalized pixel units on a touchpad - one click. Now: 120 of those units. So that's a bit less than ideal.
The change to 120 can be done, but needs the corresponding handling in the axis distance calculations.
Fixes #24 (closed)
This reverts commit 05548118.