Improved cluster api to include the current leader node

[aantono]

Added information to display the current cluster leader node to the API

[emilevauge]

@aantono hmmm not sure not having a GUID is a good thing.
How about adding a Hostname field that would be always set ?

[aantono]

@emilevauge Not having a GUID is already possible today, as one can use the --cluster.node=anything as a config, and in that case the Node identifier will not be a GUID, but whatever the supplied value is anything. So this is just a convenience instead of having to externally derive the hostname and pass it as a value. But I can do that today already via doing --cluster.node=${HOSTNAME} and it works. :)

[emilevauge]

I got it, but we prefer to set this value in a specific cluster.hostname field then, and not reuse cluster.name :) OK for you ?

[aantono]

@emilevauge As per our discussion in Slack, I've removed the part about UseHostname, so the cluster.node will have to be set externally or via config file if desired.

[mmatur]

Hi @aantono, could you please explain us why you have rebase your PR on branch v1.6 ?

[aantono]

That was done per @ldez request to be merged into 1.6 release. Is that no longer needed?

[ldez]

@aantono Are you sure? Where am I asking you this? Are you sure you do not confuse with another PR?

[aantono]

Hm... I thought we talked about it on Slack... were we talking about a different PR? Should I rebase this against master then?

[juliens]

LGTM

[ldez]

LGTM

[nmengin]

LGTM