[IMP] event: new kanban view. New! Shiny! With popcorn!

Added two features in kanban view
- having a data-routing attribute on the oe_kanban_global_click
container allow to have a custom routing instead of only
'form view' / 'edit view'. This is used for example to go to
the website view of events.
- allow type=url along with object, action, ... to have some specific
urls for links.
[FIX] doc: branch name in configuration

The branch name is used in the version switcher, so the master branch should have a version of "master".

Maybe the release could be the revision hash? Not sure how to extract it from the repo.
Merge branch 'master' of https://github.com/odoo/odoo into master-linux64