Cloud server

[Jeroen Ooms]

Hi all

I migrated the opencpu cloud server to a new host (ssdnodes.com) that
gives us much more resources for the same price.

Let me know if you run into any issues.

Also, if you want to request customizations on the cloud server,
please send a PR for this file:
https://github.com/opencpu/opencpu-server/blob/master/docker/cloud/Dockerfile

Thanks !