* @example\r
* // Loads a plugin from '/myplugin/samples/plugin.js'.\r
* CKEDITOR.plugins.addExternal( 'sample', '/myplugins/sample/' );\r
* @example\r
* // Loads a plugin from '/myplugin/samples/my_plugin.js'.\r
* CKEDITOR.plugins.addExternal( 'sample', '/myplugins/sample/', 'my_plugin.js' );\r
* @example\r
* // Loads a plugin from '/myplugin/samples/plugin.js'.\r
* CKEDITOR.plugins.addExternal( 'sample', '/myplugins/sample/' );\r
* @example\r
* // Loads a plugin from '/myplugin/samples/my_plugin.js'.\r
* CKEDITOR.plugins.addExternal( 'sample', '/myplugins/sample/', 'my_plugin.js' );\r