[SoapBundle] Moved configuration of ComplexType aliases from config to PHP objects with annotations

Before:
``` yaml
be_simple_soap:
    services_classmap:
        Cutomer: My\Bundle\Entity\Customer
        Cart:    My\Bundle\Entity\Cart
```

After:
``` php
<?php

namespace My\Bundle\Entity;

use BeSimple\SoapBundle\ServiceDefinition\Annotation as Soap;

/**
 * @Soap\Alias("Customer")
 */
class Customer
{
    // ... your PHP code
}

/**
 * @Soap\Alias("Cart")
 */
class Cart
{
    // ... your PHP code
}
```