Added function to convert seconds to runtime

lib/core/tools/ConvertFrom-TimeSpan.psm1

@@ -0,0 +1,18 @@
+Import-IcingaLib core\tools;
+
+function ConvertFrom-TimeSpan()
+{
+    param(
+        $Seconds
+    );
+
+    $TimeSpan = [TimeSpan]::FromSeconds($Seconds);
+
+    return [string]::Format(
+        'Days: {0} Hours: {1} Minutes: {2} Seconds: {3}',
+        $TimeSpan.Days,
+        $TimeSpan.Hours,
+        $TimeSpan.Minutes,
+        $TimeSpan.Seconds
+    );
+}