Allow customize entity row attributes on index page

[zorn-v]

In my project I need to highlight entity rows with different colors based on entity status.
Currently I need to copy all table_body just for add css class to row like class="status-row status-row-{{ entity.instance.status.name|lower }}"

With this patch I just need to add this in overrided template

{% block entity_row_attributes %}
    class="status-row status-row-{{ entity.instance.status.name|lower }}"
{% endblock %}

PS. After updating from 4.13, currently I need to update all my custom templates with this logic as table_body was changed.

[javiereguiluz]

Thanks @zorn-v.