Add possibility to configure custom service for query builder in doctrine orm driver

[GSadee]

It adds possibility to configure custom query builder in grid:

app_book:
    driver:
        name: doctrine/orm
        options:
           class: AppBundle\Entity\Book
           repository:
               method: [expr:service('app.custom_books_query_builder'), create]

[lchrusciel]

Thanks, Grzegorz! 🎉