Potential memory leak in the ECK Autoscaler.

[naemono]

There seems to be a potential memory leak in the ECK operator, that seems to be associated with autoscaling being enabled. Upon testing memory utilization of the operator since #357, utilization was stable (as can be seen in the graph), until autoscaling was enabled on the cluster. Since that time (~3 days) heap usage has grown from ~20MB up to ~120MB.