Zooming with scroll should centre on the pointer location not the map centre

[globau]

Steps to reproduce

1. position mouse pointer anywhere far from the centre of the screen
2. scroll to zoom in

Expected result

• the map should zoom in on the location where the mouse is positioned

Actual result

• the map always zooms in on the centre of the map

Context

BlueMap Version:
1.7.3-spigot, 3.4-spigot

The current the zoom behaviour works differently from all other mapping software I've used, including but not limited to Dynmap and Google Maps.