This commit introduce a full redesign of all JS views.  We started
basically from scratch.  The goal was to unify all the various views
under a common framework, to make them testable, to make then usable in
different conditions (in studio, or in the frontend), and to make our
lives easier.

Some important points are:
- we introduced new coding guidelines (camelCase, 80 chars width, ...)
- we have a brand new testing framework (still QUnit based)
- kanban view moved to the web addon
- calendar view (formerly web_calender) moved to web as well
- the tree view was removed
- all new code should be documented

We hope that this code is the start of a new era for the Odoo web
client, we want to have a high quality codebase, well documented, well
tested, well designed.

Work done by the framework team: mostly aab, ged, chm, dmo, qsm

Steps to reproduce:
Go to any pivot view (for example Sales > Report > Sales) and add
the current view to your personnal dashboard (in the search view: Favourites > Add to my Dashboard)
Go to the dashboard, traceback because $buttons was not defined.

opw:707296

Before this commit, when saving the pivot state in a favorite filter,
then restoring it, the row groupbys were ignored.  This commit makes
sure that we take them into account if necessary.

Before this commit, when changing measures from the favorites menu (by
selecting a filter with some pivot_measures), the measures in the
dropdown menus were not correctly updated.

This commits make sure that we update the active measures in the menu after
each changes coming from a do_search.