Updates to exception handling

[Jim Dehnert]

I updated the exception handling page to include Jason's comments and
meeting discussion, with two exceptions (due to lack of time, not lack
of desire):

  - I haven't moved anything to Level III yet (but will).

  - I haven't done a specification of struct __cxa_throw_typeinfo,
    used in the __cxa_exception definition (2.2.1) and as an argument
    to __cxa_throw (2.4.3).  My notes on this one confuse me, but it
    appears that we agreed that it should contain (or be?) a pointer
    to a function returning a (std::type_info) void*.

    Can anyone recall, or otherwise let me know the right answer?

I'm leaving now -- back in two weeks.  Remember that the meeting on
14 September is cancelled, and we'll meet next on 28 September.

Jim

-		Jim Dehnert  x3-4272