Update README.md

Author: kenogden

snippets/powershell/README.md

@@ -16,4 +16,5 @@ These scripts are only meant to be used as a reference. If you intend to use the
 Use the following commands to run the PowerShell samples.
 - `.\Get-NB-Images.ps1 -nbmaster <masterServer> -username <username> -password <password>`
 - `.\Get-NB-Jobs.ps1 -nbmaster <masterServer> -username <username> -password <password>`
+- `.\Get-NB-PolicyDetails.ps1 -nbmaster <masterServer> -username <username> -password <password> -nbpolicy <policyname>`
 - `.\Post-NB-Cleanup-Assets.ps1 -nbmaster <masterServer> -username <username> -password <password> -filter <workloadType eq 'VMware'> -cleanupTime 2018-06-29T15:18:45.678Z`