Increment and interval selectors

[basille]

The selectors for increment and interval could be improved like this:

• Invert the order: first interval, then increment (seems a more logical order to me).

• When using the keyboard and switching from one field to the next using Tab, the order goes: Increment (value) > Interval (value) > Increment (unit) > Interval (unit). It would be nice to have the unit right after the value for each of increment and interval. With the revert order suggested above, this would mean: Interval (value) > Interval (unit) > Increment (value) > Increment (unit).