[SCXML] Not allowing <initial> to be the target of a transition

We have provisionally decided to accept the following change request for inclusion in the next version of the spec.  <initial> will not have an "id" and will therefore not be able to be the target of a transition. 

 

>From Torbjorn Lager:
 
2.1 I don't think it makes sense to allow transitions into <initial>! (In other
words, <initial> should not be considered a 'transition target'.) Reasons: 1) As
far as I know (but I may be wrong), UML diagrams do not allow that, 2) it does
not seem to increase expressivity, and 3) if we don't allow it, there is no need
for <inital> to have an ID, which is a good thing...