Complete PR #290.

Currently, `atoum\scripts\runner` does not follow the Law of Demeter at several place, specially in argument handlers.
This PR resolve this.
Moreover, PHP errors triggered in a configuration file, i.e. NOTICE WARNING and so on, are not displayed to the end-user.
With this PR, these errors are now displayed.
And finally, it's possible to call CLI argument handlers via `atoum\configurator` with two equivalent syntax to avoid BC break:
```php
$script->noCodeCoverageForNamespaces(array('foo', 'bar'));
$script->noCodeCoverageForNamespaces('foo', 'bar'); // strictly equivalent to the previous line
```