This package contains the API for adding content to the help search functionality
and is responsible for indexing all contents of the help system. To add content, a
plug-in must extend the SearchParticipant abstract class and point to it
using the org.eclipse.help.search.searchParticipant extension point.
The package also provides an abstract class that extends LuceneSearchParticipant
called SearchParticipantXML which adds functionality for parsing XML
documents.