Update rule documentation

Author: Kapil Borle

RuleDocumentation/UseIdenticalMandatoryParametersForDSC.md

@@ -4,13 +4,24 @@
 
 ## Description
 
-The `Get-TargetResource`, `Test-TargetResource` and `Set-TargetResource` functions of DSC Resource must have the same mandatory parameters.
+For script based DSC resources the `Get-TargetResource`, `Test-TargetResource` and `Set-TargetResource` functions must have identical mandatory parameters that are also the keys in the corresponding `mof` file.
 
 ## How
 
-Correct the mandatory parameters for the functions in DSC resource.
+Make sure all the keys have equivalent mandatory parameters in the `Get/Set/Test` functions.
 
 ## Example
+Consider the following `mof` file.
+```powershell
+class WaitForAny : OMI_BaseResource
+{
+    [key, Description("Name of Resource on remote machine")]
+    string Name;
+
+    [required, Description("List of remote machines")]
+    string NodeName[];
+};
+```
 
 ### Wrong
 
@@ -33,7 +44,7 @@ function Set-TargetResource
     (
         [parameter(Mandatory = $true)]
         [String]
-        $TargetName
+        $TargetName # this should be Name
     )
     ...
 }