Implement the ability to create label/value filters for pivot tables, similar to the row filters available in Excel.
**Description** Excelize can currently set a page filter for a pivot table, but does not seem to support creating label/value filters. When running the sample code from https://xuri.me/excelize/en/pivot.html#AddPivotTable there is a page filter set for region, but clicking on the row filter in excel allows user to create label or value filters. For example,   Adding this value filter results in the following xml in pivotTables/pivotTable1.xml (including data above and below the filters node for context) ``` <pivotTableStyleInfo name="PivotStyleLight16" showRowHeaders="1" showColHeaders="1" showRowStripes="0" showColStripes="0" showLastColumn="1" /> <filters count="1"> <filter fld="0" type="valueGreaterThan" evalOrder="-1" id="3" iMeasureFld="0"> <autoFilter r