Restructure of pester test layout

This restructuring moves tests to a directory name which matches the module
in which the cmdlet resides which should improve the discoverability of a
specific test.
For tests which are not about cmdlets in a module, new directories have been
created to make those tests easier to find as well

test/powershell/CmdletExample.Tests.ps1

@@ -1,6 +0,0 @@
-try {
-    Push-Location $PSScriptRoot/../../docs/cmdlet-example
-    ./SendGreeting.Tests.ps1
-} finally {
-    Pop-Location
-}

test/powershell/Host/ConsoleHost.Tests.ps1

@@ -1,6 +1,7 @@
 using namespace System.Diagnostics
 
 Describe "ConsoleHost unit tests" -Tag 'Slow' {
+
     $powershell = Join-Path -Path $PsHome -ChildPath "powershell"
 
     Context "CommandLine" {