/* tracks_load.php  12/03/2022
			galvanises loading of tack thmb & json files
			see https://stackoverflow.com/questions/11719045/how-to-retrieve-files-on-a-directory-in-list-using-php
called in menu.js
			combination of dir.php & tracks_json.php
			this must not be in ./require;  must be .php 
			
	V.1 04/07/2024	path to common tracks directory
									trackdata & trackjson in the working directory are Symbolic link directories 
									see  "NB_trackdata_+_trackjson_are_symbolic_links__see_inside.txt" for details

*/


var 			thmb_files  = [];

var 			json_files  = [];