Added Timestamp Bucket example

Examples/Grouping/TimestampBucket.ps1

@@ -0,0 +1,39 @@
+$data = ConvertFrom-Csv @"
+Timestamp,Tenant
+10/29/2018 3:00:00.123,1
+10/29/2018 3:00:10.456,1
+10/29/2018 3:01:20.389,1
+10/29/2018 3:00:30.222,1
+10/29/2018 3:00:40.143,1
+10/29/2018 3:00:50.809,1
+10/29/2018 3:01:00.193,1
+10/29/2018 3:01:10.555,1
+10/29/2018 3:01:20.739,1
+10/29/2018 3:01:30.912,1
+10/29/2018 3:01:40.989,1
+10/29/2018 3:01:50.545,1
+10/29/2018 3:02:00.999,1
+"@ | Select-Object @{n = 'Timestamp'; e = {get-date $_.timestamp}}, tenant, @{n = 'Bucket'; e = { - (get-date $_.timestamp).Second % 30}}
+
+$f = "$env:temp\pivottest.xlsx"
+Remove-Item $f -ErrorAction SilentlyContinue
+
+$pivotDefParams = @{
+    PivotTableName = 'Timestamp Buckets'
+    PivotRows      = @('Timestamp', 'Tenant')
+    PivotData      = @{'Bucket' = 'count'}
+    GroupDateRow   = 'TimeStamp'
+    GroupDatePart  = @('Hours', 'Minutes')
+    Activate       = $true
+}
+
+$excelParams = @{
+    PivotTableDefinition = New-PivotTableDefinition @pivotDefParams
+    Path                 = $f
+    WorkSheetname        = "Log Data"
+    AutoSize             = $true
+    AutoFilter           = $true
+    Show                 = $true
+}
+
+$data | Export-Excel @excelParams