Generating tiles from GeoTIFF takes time to be generated

[MBoustani]

When user import a GeoTIFF and head to Data Visualization page, on the backend gdal2tiles code being used to generate tiles from GeoTIFF to be able to show it on openstreets map. However; generating tiles form GeoTIFF takes time (depends on size of GeoTIFF) and won't notify user to wait or refresh page to view tiles. Need to find a solution for it.