Ensure generated tokens are integers
update topology if needed when a new cluster dir is set

when setting a new cluster dir the topology is lost
this affects multi-dc ccm cluster when new cluster directory is set
Merge pull request #115 from thobbs/ensure-int-tokens

Ensure generated tokens are integers
Merge pull request #116 from knifewine/dont_lose_topology_on_upgrade

update topology if needed when a new cluster dir is set