Introduce a drift-check loop

[bygui86]

Hi everybody,

as mentioned by @alexei-led in this issue #148, currently KubeIP performs a single one-shot action at the startup, then simply going idle.
I suggest to add a loop to check for possible drifts and in case fix them immediately.
For example someone could accidentally remove an IP address from a VM, or replace a reserved an IP address with another one. Such action could disrupt and compromise regular functionalities.

If such drift-check loop is added, then it would make sense to add a K8s liveness probe as well.