Add AutoWatch override to bulk change operations

When users who have AutoWatch enabled add comments to a large number of issues through a bulk change, they will become Watchers for every issue on the list. It's extremely easy to forget that this will happen when you are performing a bulk-change.

Currently, the only workaround for this is to disable AutoWatch in your profile before doing the bulk operation, and then re-enabling it afterwards...and most users only learn to do this because of a painful first experience where they become Watcher on thousands of issues (yes, I am one of those users!).

There is already an override checkbox on bulk-change to avoid sending e-mail notifications from the update...it would be very helpful if there were something similar to override AutoWatch for a bulk operation.