Feature request: Aggregate multiple umaps

[timotoots]

Is your feature request related to a problem? Please describe. We try to aggregate multiple umaps together. Multiple partners manage their individual maps, but we would like to make one combined map with all partner data together.

Describe the solution you'd like Allow dynamic import of another map in umap format.

Describe alternatives you've considered It seems it could be possible to use "remote data" with GeoJSON format, but it means another umap should be able to give it out. There is a way to download GeoJSON, but not dynamically link to it.

Additional context Thanks for the great software!