[FIX] gamification: allow having False or 0 values as result of a computation.
[FIX] mail: avoid crashing message_post if the subtype does not exists anymore.
Using xmlid_to_res_id, subtype_id will be False if not found.
[REF] gamification: add batch mode, improve some views, remove inprogess_update state (replaced with boolean 'to update')
[FIX] mail: res_users post: fixed partner_ids computation, could receive
a list of ids, or a list of commands. Both cases should be taken into account.
[ADD] gamification: realtime badge to recieve badge without closing the challenge
[MERGE] sync with trunk
[MERGE] gamification: add batch mode, improve some views, remove inprogess_update state and "realtime" (using cron) badge to recieve badges without needing to close the challenge