Implement file storage on Google Cloud

[m-mohr]

Currently, the driver has its own file storage, but GEE uses Google Cloud Storage. We should try to find a way to connect to the Google Cloud Storage and not use our proprietary implementation as this limits us in importing and exporting files before/after data processing. I'll probably need some help from the GEE engineers to figure out the details. We are already connected to a GCS bucket using the package "@google-cloud/storage", which is used to download the dataset catalogue. Maybe we can re-use that library.

[edzer]

More in general, effective clouds use some kind of special storage; aws e.g. S3. I believe S3 is also found in non-aws clouds.