ErrorHandling: improve argument handling for debug info

`var_dump` was the wrong function to call for objects, as it would just output all object
data to the output buffer... Let's generalise and use `var_export` instead :-)

models/ErrorHandler.php

@@ -100,10 +100,12 @@ class ErrorHandler
 			{
 				foreach ($call['args'] as $j => $arg)
 				{
-					if (is_array($arg))
-						$args[$j] = print_r($arg, true);
-					elseif (is_object($arg))
-						$args[$j] = var_dump($arg);
+					// Only include the class name for objects
+					if (is_object($arg))
+						$args[$j] = get_class($arg) . '{}';
+					// Export everything else -- including arrays
+					else
+						$args[$j] = var_export($arg, true);
 				}
 			}