Gauge API *_EX1() function links missing in sidebar index

Minor issue, just a bit confusing. As per the title, while the new *_EX1()
functions (trigger|register|unregister)_key_event[_handler]_EX1(), are
documented, they don’t appear in the sidebar index. Both in the SU10 release
and current flighting versions of the docs. Thanks, -Max

Thanks for pointing this out! They’ll be added to the table of contents for
the public SU11 release.