Classes for two-way FreeMarker-JSP integration. It contains both a JSP
custom tag that allows embedding of FreeMarker templates inside JSP
pages, as well as the infrastructure that allows JSP custom tags to be
used inside FreeMarker templates.
An instance of this class should be registered as a <listener> in
the web.xml descriptor in order to correctly dispatch events to
event listeners that are specified in TLD files.