[WIP] [RFC] Product translation (Prezent)

This is a second approach using Prezent, please look at issue #2018
Instead foreach do:
```php
$locale = $this->localeRepository->findOneBy(array('enabled' => true, 'code' => $this->defaultLocale));
if (!$locale) {
    throw new \Exception('Default locale is not available!');
}

return $locale;