Prior to this commit, the section in **about_Format.ps1xml** incorrectly
explained the `<WideEntry>` tag and did not mention the `<WideItem>` tag
at all.

This commit updates the section for clarity and documents the
`<WideItem>` tag and its valid child tags.

Prior to this commit, the Managing Services sample in the conceptual
documentation included example code using the **ComputerName** parameter
for `Get-Service`, but that parameter was removed from the `*-Service`
cmdlets in PowerShell 6.0.

This commit updates the documentation to distinguish between Windows
PowerShell and PowerShell for managing remote services and clarifies
how to do so.