Add parameter validation functions and enhance tests for configuration data

Private/Assert-ConfigurationDataParameterNumericValue.ps1

@@ -0,0 +1,21 @@
+function Assert-ConfigurationDataParameterNumericValue {
+    [CmdletBinding()]
+    Param(
+        [Parameter(Mandatory=$true)]
+        [string]
+        $Name,
+
+        [AllowNull()]
+        $Value
+    )
+
+    if($null -eq $Value -or $Value -is [bool] -or ($Value -isnot [ValueType])){
+        throw "Parameter [$Name] value [$Value] is not numeric."
+    }
+
+    try {
+        [void]([decimal]$Value)
+    } catch {
+        throw "Parameter [$Name] value [$Value] is not numeric."
+    }
+}