Dont exit the update ip function if the old and new interfaces are the same

Dont exit the update ip function if the old and new interfaces are the same
since if they are the same for whatever reason this triggers the system
to go into an infinite loop and is unrobust

The scriptds have been changed instead to be able to cope with this
situation for enhanced robustness

During takeover_run and when merging all ip allocations across the cluster
try to kepe track of when and which node currently hosts an ip address
so that we avoid extra ip failovers between nodes