KUBE_PING should read old env variables and should warn

While I was upgrading Infinispan cluster on docker, I realised I was using old environment properties. These were neither read nor was any WARN messages being reported.

The code should read the current properties and if not present should try to read the old ones and assign them. Then, we should check if both new and old properties are in use and we should also check if only old ones in use. Both scenarios should warn the user.