WEB: Add error handling about missing required fields

In the new data model, some field operate as keys for other parts of the model.
This now performs some validations and will throw an error if fields are missing.

For example: a Game must have an Engine, but does not require datafiles

include/Objects/BasicObject.php

@@ -16,6 +16,11 @@ abstract class BasicObject
         $this->name = $data['name'];
     }
 
+    public function __toString()
+    {
+        return $this->getName();
+    }
+
      /* Get the name. */
     public function getName()
     {