Add quotes around ArgumentList to avoid PowerShell error

PowerShell chokes with a "Missing argument in parameter list" error
on Windows Server 2012 R2 Standard without quotes around the arguments
given to ArgumentList.
Set ArgumentList with explicit array

Having no quotes or surrounding the ArgumentList with quotes both appear to have issues. Tested with a user whose home folder is "C:\Users\some user" (since the space causes issues). Hopefully using an explicit array should work in all cases for everyone.
Merge branch 'terje-argumentlist'