Comment 3 for bug 1657350

Then we should consider UX of a few nodes deletion. We need to get user information that it is possible to remove 1 node only at the same time:

1) it can be described in the error message
2) or Remove button can be hidden on UI if some node already removing (cluster has running 'node_deletion' task).
3) Does 'node_deletion' task support deletion of a few nodes at the same time? If yes, we can think about batch node removal from UI.