[ADD] ir_actions add logging to server actions

The log(message, level='info') function will create ir_logging records, useful
to debug server actions.

Closes: #928
[IMP] account, restrict removal of accounts used on account.tax

Closes: #789
[IMP] ir.attachment access right, use write mode of related object

For related models, check if we can write to the model, as linking
or unlinking attachments can be seen as an update to the model.

Courtesy of Vincent Vinet

Closes: #1035