Add XSL for FOP that overrides indexing
user
```xslt
<?xml version='1.0'?>

<!-- ===================== CHANGE LOG ================================ -->
<!--                                                                   -->
<!-- 08 May 2019 KJE: Original creation                                -->
<!-- 16 May 2019 KJE: Changed name of plug-in                          -->
<!--                                                                   -->
<!-- ================================================================= --> 

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
                version="2.0">

    <xsl:import href="oasis-spec-topic2fo-shell.xsl"/>
    
    <xsl:import href="plugin:org.dita.pdf2.fop:xsl/fo/index_fop.xsl"/>
    
    <xsl:output method="xml" encoding="utf-8" indent="no"/>

</xsl:stylesheet>```
assistant