Update Backup-GroupPolicy.ps1

[SamErde]

1. Replaced WMI query for the domain name with a reference to the system environment variable for the current user's domain. Avoids the expense of running a WMI query.
2. Removed the Mandatory attribute from the Server parameter. This was missing a Boolean setting, and compensating code is added below.
3. Since your blog post mentioned thoughts around using "Server" vs "DomainController" or "DC" for the parameter name, I though you might like an alias for this!
4. Added tab autocomplete for the server parameter, which fills in domain controller names automatically! Lines
5. Gets a domain controller name for the Server parameter if no server parameter is specified.
6. Checks to see if $UpdatePath does not exist, creates the new backup folder if it does not exist yet. No errors now if the folder already exists. My goal is to be able to run this multiple times per day, if necessary.
7. Grammar police removed the apostrophe from "GPOs"

[SamErde]

This will pull the current domain from the system environment variables instead of processing a WMI query.

[compwiz32]

thanks for the code adds!