-using dom parsing to scrap wikipedia content
-added Item and Title classes.
-new related items are generated lazily breadth first
-use data_gen_classes for all classes code.
-data_gen.js communicates with data_gen.php.
-note that the limit sent to data_gen.php is really a limit, not the number of items to be generated

//TODO:
-handle wikipedia redirect and ambiguity
-connect edges
-make compatible with oculus