Remove unimplemented Management cmdlets from Unix

These are not currently implemented and so should not show up as
available.

The *-Computer cmdlets are already not compiled for Unix (and so not
available), so let's not declare them in the manifest.

The Get-ComputerInfo cmdlet does not work on Unix and so should not be
made available.

Test-Connection depends on an unavailable WMI provider.

Get/Set-TimeZone are not yet ported.

test/powershell/Modules/Microsoft.PowerShell.Management/Unimplemented-Cmdlet.Tests.ps1

@@ -0,0 +1,30 @@
+Describe "Unimplemented Management Cmdlet Tests" -Tags "CI" {
+
+    $Commands = @(
+        "Get-Service",
+        "Stop-Service",
+        "Start-Service",
+        "Suspend-Service",
+        "Resume-Service",
+        "Restart-Service",
+        "Set-Service",
+        "New-Service",
+
+        "Restart-Computer",
+        "Stop-Computer",
+        "Rename-Computer",
+
+        "Get-ComputerInfo",
+
+        "Test-Connection",
+
+        "Get-TimeZone",
+        "Set-TimeZone"
+    )
+
+    foreach ($Command in $Commands) {
+        It "$Command should only be available on Windows" {
+            [bool](Get-Command $Command -ErrorAction SilentlyContinue) | Should Be $IsWindows
+        }
+    }
+}