Changed translation domain for label

The label 'label_type_contains_words' does not exists in SonataAdminBundle translations. This is a bundle-specific label, and it is defined in the local translation file.
Added translation for label_type_contains_words

This label is used in Form/Type/Filter/ChoiceType.php class.
Added translation for label_type_contains_words

This label is used in Form/Type/Filter/ChoiceType.php class.
Typo
Merge pull request #280 from eiannone/patch-2

Fixed translation for label_type_contains_words