Handler-case implementation.
Handler syntax for match.
Static exceptions can exit try...with blocks.  Currently works only in bytecode.

git-svn-id: http://caml.inria.fr/svn/ocaml/branches/static_exceptions@13222 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

Conflicts:
	typing/typecore.ml
Static exceptions can now escape try blocks also in native code.

git-svn-id: http://caml.inria.fr/svn/ocaml/branches/static_exceptions@13223 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

Conflicts:
	typing/typecore.ml