Intialize this plugin. The plugin can use static object in the client such as the ClientContext to register itself with the Wonderland environment. In addition, a plugin is given the LoginManager for the WonderlandServer it is associated with.
Plugins are loaded after the client logs in to the given server, but before any WonderlandSessions have been created. Plugins that need to use a WonderlandSession can either create their own or (more typically) install a SessionLifecyclyListener to wait for session creation.
@param loginManager the loginManager representing the server thisplugin is connected to.