CPP12 — _name and _rep_id

Question: do I need to deallocate the string returned by Exception::_name()
and Exception::_rep_id() or not? The spec doesn't say...

Given that these are PIDL, and that the return value is const char *
(rather than non-const char *), I'd say that I shouldn't have to deallocate
the return value. But I think we should clarify this in the spec.

Also, the Exception class in section 1.41.7 doesn't show the _name and
_rep_id members, so we need to add them there.

Further, Exception doesn't show up in section 1.23 (Mapping of Pseudo
Objects). I suspect that we need to add Exception there as well and
mention the exception to the memory management rules? Another interesting
thing is that, if Exception is a pseudo object, then UserException and
everything derived from it is also a pseudo object. But, user exceptions
can't be pseudo objects. But, if they are not pseudo-objects, we can't
really make special-purpose memory managment rules. Sigh...

see below