cert_distribute.sh script should allow customers to input a list of client nodes

In the current implementations, the cert_distribute.sh shell script at levels 8.1.21 and 8.1.22 queries the Storage Protect server for all its Storage Protect client nodes, does some filtering to select only supported platforms, and then will associate the queried nodes to the cert_renew_* schedules defined by cert_distribute.sh.
Using this implementation/ design, the cert_distribute.sh script is unable to detect that multiple Storage Protect client node names belong to the same hosts, maybe running multiple Storage Protect client schedulers, connecting to the same Storage Protect server.
As a result, multiple Storage Protect client schedulers will be associated to the same set of cert_renew_* schedules. Because of this, multiple client schedulers will execute the same scheduled command, trying to create and write into the same new client crt file in parallel. This will result into a corrupted new client crt file and invalidates the overall process of distributing the new SSL certificate to the Storage Protect clients.
An easy solution to this would be to allow customer to create a file containing a list of all Storage Protect client nodes which should receive the new SSL certificate. 
The cert_distribute.sh script should use the list of Storage Protect client node names out of the customized input file instead of querying all Storage Protect client nodes from the Storage Protect server itself. To ensure the customer only specified valid/ support Storage Protect client nodes the cert_distribute.sh script may validate the customized list against the Storage Protect server.