Manage Certificates > Adding New Nodes should mention nodes that were removed being re-added

In this section of the docs we tell users what they need to do when adding a node to a cluster that uses user uploaded certs.

In addition we should explicitly call out the case of a node that was removed from the cluster and then later re-added. This happens because when a node is removed from a cluster its configuration is essentially wiped out - it becomes more or less just like a brand new node.

We should call out the fact that nodes that were removed and are being re-added need to have the CA cert and the node cert loaded just like brand new nodes.