Transfer multiple datasets to another hosting platform

[hermancollin]

I am in the process of curating and eventually uploading some of our datasets to a public platform called DANDI archive. They support BIDS, so the transition will be simple, but we need to de-duplicate the data from our internal database. In #351, I see that we can have a mirror to public datasets, maybe this would be the way to go. Here is a list of what I plan to upload:

• data_axondeepseg_tem
• data_axondeepseg_bf_training
• data_axondeepseg_wakehealth_training
• data_axondeepseg_vcu
• data_axondeepseg_cars
• data_axondeepseg_stanford

also, this one (but it's hosted on github here)

• data_axondeepseg_sem