initialize the plugin, automatically called during the core initialization process
ClassMethod finish()
called when this object is destroyed
getCore() → $core
returns a singleton Foswiki::Plugins::LikePlugin::Core object for this plugin;
a new core is allocated during each session request; once a core has been
created it is destroyed during finishPlugin()
ClassMethod afterRenameHandler()
called by the core whenever a topic or attachment is renamed
ClassMethod registerAfterLikeHandler($sub)
register a callback handler to be called whenever a like is performed