Exceptions in Uninterruptible code should result in immediate fatal errors

Uninterruptible code is not allowed to raise exceptions (hardware or software). This represents a severe programming error.

Modify the exception delivery code in VM_Runtime.deliverException such that any hardware exception that is raised in uninterruptible code results in an immediate assertion failure and VM state dump. This should give us cleaner error behavior than stumbling forward for a while, attempting to deliver the exception, and then exploding later.