[perl #34970] [PATCH] fixed getattribute to throw real "Attribute not found" exception

[Cory Spencer]

# New Ticket Created by Cory Spencer
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The getattribute opcode previously threw an internal exception when an
attribute wasn't found in a class. This type of exception is uncatchable
with Parrot exception handlers. The included patch allows a real,
catchable exception to be thrown in these cases.

[Jens Rieks]

Thanks, committed with some tweaks to not break t/pmc/objects.t.
Please test your patches prior to submission.

NB: I've skipped the changed comments, please review them

jens