- create many-to-many relationships between the user table and
attributes tables (manufacturer / model / location / status / action)
- add a checkbox as the first column of the attributes table to add or
remove an attribute to the favorites
- add a new page to display the favorite attributes

JIRA INFRA-283

- Remove QRcodes page
- Add Status to attributes page (only allow admin to add new statuses)

Actions QR Codes not visible anymore. Required ones shall be put on the
page where they are used.

- Main blueprint used to declare custom views for all blueprints.
(keep inventory blueprint cleaner)
- Add url_prefix to each blueprint

This can be done via the Admin interface but this latter shall be
restricted to admin users. This simple page allows the group "create"
to easily add new Manufacturer, Model or Location.