Round double-tap and two-finger tap zoom gestures to the nearest integer zoom level. This has the benefits for raster tiles, as well as styles with zoom-based functions.
This results in a wider possible zoom range — ~0.5-1.5:
Old: z4.6 → z5.6 (+1.0), z4.4 → z5.4 (+1.0)
New: z4.6 → z6.0 (+1.4), z4.4 → z5.0 (+0.6)