Add the possibility to exclude the headings aggregation from the TOC

The PDF template uses the pdftoc macro which has a depth parameter, see https://github.com/xwiki/xwiki-platform/blob/master/xwiki-platform-core/xwiki-platform-export/xwiki-platform-export-pdf/xwiki-platform-export-pdf-api/src/main/java/org/xwiki/export/pdf/macro/PDFTocMacroParameters.java . You could try to create a custom PDF template that uses depth=1 .