[IMP][TEST] event: auto confirmation option, allowing to
automatically confirm events. In a simple flow it is usefull to automatically
confirm event and registrations.

[TEST] event: moved draft2done test into a unittest, easier to finely tune
in order to test the auto confirm option. Moreover this gives a basis to
further add python tests in the module. Hooray.
Merge branch 'master' of https://github.com/odoo/odoo into master-linux64