In Drupal 7 module development, I could include a custom inc, api, or php class file using the file= directive in the module.info file or the drupal_load_included() function.
With D8 using PSR, what is the proper way to package up a "plain ole PHP object" and reference it in
DefaultController.php? Think something like:
$a = new POPO();.
Is just giving the PHP file containing the class a
namespace sufficient? How does the controller (or module in general) know to reference or scan for that class?