[Reviewer Matt] Subject OPTIONs to overload controls

Matt

Can you review the rest of the fix to issue630 - to get OPTIONs subjected to overload controls and to enable deadlock detection on the message queue.  This also changes the load monitor parameters to what they should be before they were inadvertantly changed.

The is a corequisite clearwater-infrastructure change to the poll-sip job to treat overload responses as acceptable, so I'll create a pull request for that as well.

Mike
Do we get any diagnostics here?  Would we be better to `abort()`?