Phase out node with a click

[synhershko]

It will be very cool if, similarly to how we can drag-drop shards today on nodes, mark a node for phasing it out. Behind the scenes Kopf could then add exclude tags to all indices (and after the node is removed, remove those exclude tags).

[lmenezes]

@synhershko hum... I guess this could work, even though as kopf has no real persistence(browser only), it could be a risky issue keeping track of that.

On the other hand, this weekend I started playing around with the idea to have a successor for kopf, given that es will no longer support site plugins and I don't like the idea of integrating this into kibana.

If I finally decide to move this way, I will leave kopf in maintenance mode only and slowly migrate what already exists into the new one, otherwise, this should be easy enough to do :)