Make some service to share public keys between servers to rsync without being prompted for password

[maxsumrall]

My initial idea is for one main server to be maintaining a directory of public keys, and each worker server/file server to update their authorized_keys file when a new server is added.

Another way is for each job message to include the the servers public key, and the worker/fileserver adds the keys each time. This might be easier to implement.