[FIX] ir_attachment: in check, values could coutain a
False res_model; no need to check self.pool[False], obviously. We consider void attachments
as being accessible, because no related document exists.

Hint: backport me in 7.0
[FIX] multicorn: WorkerLongPolling watch for parent change
[IMP] multicorn: WorkerLongPolling log into logger
[IMP] multicorn: Workers closes unwanted sockets