Fix missing Tester\Dumper

I get `Fatal error: Class 'Tester\Dumper' not found in .....\compileWarning.inc.php on line 3` without this fix. Only with PHP 5.3.6, 5.4.0, but PHP 5.5.6 is OK without this.

I tried to write a test for this case:
- classes must be autoloaded (like with composer)
- file with error must be required

Maybe any other compile-time errors prevents autoloader to load a class too, but I didn't find one.