duplicate delivery of state_entry if a region is restarted just after
saving the script. Changes script state saves to no longer abort long-
running event handlers. Queues the save instead. Adds shutdown handler
to save script state on irderly shutdown
* This is a HUGE OMG update and will definitely have unknown side effects.. so this is really only for the strong hearted at this point. Regular people should let the dust settle.
* This has been tested to work with most basic functions. However.. make sure you back up 'everything' before using this. It's that big!
* Essentially we're back at square 1 in the testing phase.. so lets identify things that broke.
engines that want to use the XEngine's instance handling and state
persistence can do so. IScriptInstance is optional, but it does
require the SmartThreadPool if it is used.
