Cluster installation prechecks should query ssh keys and passwordless prompts are configured as needed

[mrolyat]

The role prechecks should query all cluster nodes ssh key exchange and passwordless prompts are as expected prior to running the playbook. This will prevent hangs and failures to ensure the environment is configured properly.

See 'mmnetverify' or other options to run the query from install node to all nodes as well as all nodes to other nodes as well as to themselves.

[rajan-mis]

As per our design and discussion , we are not planning to add any hard validation in the open source code. user needs to define inventory and check node accordingly. we will have real validation and mmnet check in the toolkit.

We have already added example playbook to validate ssh and node states . user can write their own playbook using this sample playbook. https://github.com/IBM/ibm-spectrum-scale-install-infra/blob/dev/samples/playbook_cloud.yml