Purpose of this commit is to give description more "business oriented"
because those descriptions appears in Odoo Studio which is supposed to be used by end users, not only by developers.
Related Task ID : 37311
Before this rev. one could set the report layout on the company using a
hardcoded list (background, clean, standard, etc.). Other modules (typically
accounting modules) could add options in this list. The used template was built
on the layout key.
Now, the layout is a many2one field to a newly created model `report.layout`,
which is linked to a view with the layout architecture.
This gives more control to customize reports and create a new layout (without
creating a python module that extend the layout selection).
Nimesh Jethva