Add default_vis option to cog_tile() function

[giswqs]

By default, Map.add_cog_layer() adds a rescale parameter to a single band raster to achieve an optimal visualization. This might not be ideal for some COG files with a built-in colormap in it, such as as land cover maps. This PR adds a default_vis parameter to the function to force leafmap to use the built-in colormap from the data.

Update your package using leafmap.update_package() and restart the kernel to take effect. This improvement will be included in the next leafmap release.

import leafmap
m = leafmap.Map()
url = 'https://data.mundialis.de/geodata/lulc-germany/classification_2021/classification_map_germany_2021_v01_COG.tif'
m.add_cog_layer(url, name='LULC Germany 2021', default_vis=True)
m

[neteler]

Thanks for this quick bugfix!