"Humanize" the State Event Restriction List

[David Stocker]

Currently, the State Event Script uses a numeric Memetic restriction, 0, 1 or 2. This is in no way human readable and presents a UX problem for the designer. Currently from setStateEventScript()

            if state == 0:
                self.initScript = function
            elif state == 1:    
                self.execScript = function
            elif state == 2:    
                self.terminateScript = function  

These integer values should be strings:
initialization
execution
termination

This should be done before the first tag is created, so that we don't introduce incompatible changes.