JukeAlert - Added snitch detail and snitch culling
Added final procedure which cursors over snitches and deletes their detail
records and finally their actual snitch record.  Configurable via the
two new settings values.  If the log or non-logged setting values are
set to 0 (default value) then no snitch culling takes place.
If they are set to a positive non-zero number of days, they will take place
at the first restart of the server after a snitch has 'ran out of time'
based on its last-visit date.