Encode framework-specified operation ID into CSI volume name.

Currently, SLRP uses the internally-generated operation UUID as CSI volume creation name, which brings extra difficulty for debugging because users have to go through logs to figure out the operation UUID for a given CREATE_DISK call.

Instead, we could encode the framework-specified operation ID into the volume name. To ensure the uniqueness of each volume name, we can use the following schema:

mesos-<base64-urlsafe-encode(operation-uuid)>.<framework-specified-operation-id>

The prefix before the framework-specified operation ID would be 29 characters long.

We can consider not having the mesos- prefix to even shorten it, but it might not be a bad idea to have that prefix reserved for Mesos.