initialize the plugin, automatically called during the core initialization process
lateInitPlugin()
Foswiki::Plugins::VERSION >= 2.6
register all known meta data now that all plugins have been init'ed
getCore() → $core
returns a singleton Foswiki::Plugins::MetaDataPlugin::Core object for this plugin; a new core is allocated
during each session request; once a core has been created it is destroyed during finishPlugin()