Improve and fixing managing nodes section
Improve and fixing managing nodes section

This section of the docs ihave multiple incorrect statements and information. This commit tries to improve it. Further work is required, as it doesn't cover the full end to end for the user.

vikram-redhat/openshift-docs,vikram-redhat/openshift-docs,vikram-redhat/openshift-docs,vikram-redhat/openshift-docs,vikram-redhat/openshift-docs