Exception handling documentation

[Jim Dehnert]

HP has released the IA-64 runtime conventions documentation on the web at:

	http://devresource.hp.com/devresource/Docs/Refs/IA64Runtime.pdf

and I have a copy for SGI folks at:

	http://baalbek.engr.sgi.com/dehnert/docs/psABI/IA64Runtime.pdf

Thank you Cary!  This means that we now have the exception handling
documentation and can discuss it without NDA.  (However, we still do
not have Intel's promised description of how they intended to use it
for C++, and those details aren't in the general conventions.)

-		Jim Dehnert  x3-4272