list template should have parent() in blocks

[makasim]

Hi.

Thanks for very good and useful bundle. It is great one.

I have an idea how to tweak layout a bit.

it is often need only small changes like adding a custom css file.

now for such think I need copy past WhiteOctoberAdminBundle::layout.html.twig and add the one line of code.

but if you add parent() to list.html.twig for example I can easy extend your layout redefine content block and add there custom code.

thanks.