add "Zoom Native Resolution" context menu botton for map view raster layer

[Andreas Janz]

Zoom to native resolution for the whole MapView is nice!

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The first raster layer (hires_berlin in this case) seams to be used as reference. Now it would be nice to have the same button available at each map view raster layer. This way, I could also easily zoom to enmap_berlin native resolution.

[Andreas Janz]

Removing version: 3.10 (automated comment)