use Atlas instead of local MongoDB server

[gcschmit]

Consider using Atlas to host the MongoDB server for SPOT rather than using a local server. This would make it easier to debug and transfer data since we could leverage Atlas' web interface rather than doing everything via the command line. In addition, I'm not sure if the Compass application can connect to the local server (it may be able to if we open the port, but that is a security vulnerability). The Compass application is also helpful for debugging.