The 'new' (read: the classes not in the 'compatibility layer section')
classes of the kanban views did not allow to cleanly separate an image
header from a content container.
This commit adds such a container, allowing a very simple layout that
should work all the time for a typical 'card with left image and right
content layout':
```xml
<div class="o_kanban_record oe_kanban_global_click o_kanban_record_has_image_fill">
<field class="o_kanban_image_fill_left" name="image_128"
widget="image"
options="{'zoom': true, 'background': true, 'preventClicks': false}"/>
<div class="o_kanban_record_details">
<div class="o_kanban_record_top">
<div class="o_kanban_record_headings">
<strong class="o_kanban_record_title">
<field name="x_name"/>
</strong>
</div>
</div>
<div class="o_kanban_record_body">
<!-- some fields here (e.g. tags,...) -->
</div>
<div class="o_kanban_record_bottom">
<div class="oe_kanban_bottom_left">
<!-- some fields here (e.g. kanban status,...) -->
</div>
<div class="oe_kanban_bottom_right">
<!-- some fields here (e.g. user image,...)-->
</div>
</div>
</div>
</div>
```
Before this commit, the absence of a container for the right side meant
that the top/body/bottom were flex-growed in a flex-direction: row
element, appearing as 3 columns instead of rows.
Damien Bouvy
18e06fa90a