Create custom form themes for Dachcoms Formbuilder Plugin in Pimcore

From time to time you want to overwrite the default templates for forms in pimcore.
I had some problems to find the information I need as they are spreaded widley.

To get it to work it should look like this:

Filestructure

# src/AppBundle/Resources/config/pimcore/config.yml
form_builder:
form:
templates:
ivoclar_div_layout:
value: 'my_form_div_layout.html.twig'
label: 'Custom form layout'
default: true
{# tempaltes/bundles/FormBuilderBundle/Form/Theme/Macro/my_form_div_layout.html.twig #}
{% macro form_builder_form_head() %}
{% endmacro %}

{% macro form_builder_form_foot() %}
{% endmacro %}

{% macro form_builder_form_message(flash_messages) %}
{% if flash_messages is not empty %}
{% for label, messages in flash_messages %}
{% for message in messages %}
<div class="message message-{{ label }}">
{{ message|raw }}
</div>
{% endfor %}
{% endfor %}
{% endif %}
{% endmacro %}
{# tempaltes/bundles/FormBuilderBundle/Form/Theme/my_form_div_layout.html.twig #}
{% extends "form_div_layout.html.twig" %}

{%- block widget_attributes -%}
id="{{ id }}" name="{{ name }}"
{%- if disabled %} disabled="disabled"{% endif -%}
{%- if required %} required="required"{% endif -%}
{{ block('attributes') }}
{%- endblock widget_attributes -%}