Remove zoom mode

[cmkohnen]

Since we have finer control over zooming now, this mode can be dropped imo.

[sstendahl]

Although there's indeed more ways to zoom now, the touchpad and scrolling gestures all do zoom equally in all directions, so it's not possible to zoom along one axis only. Personally, I think it can be very convenient to be able to draw a zoom box around a certain part of the plot somehow. Another issue is that the new zoom controls don't work on PC's if you don't have a mouse with a scroll wheel.

The same is true for panning by the way. Which can now also be accessed using the middle mouse button plus moving, but also there it's the case that this does require that you don't use a very basic mouse that only has two buttons. They're somewhat rare nowadays but still in use.

[cmkohnen]

Well personally I never really used this zoom mode. But if it is still useful, as you describe, I'm not at all against keeping it.