Use yaml2obj to generate more test cases

[woodruffw]

Similar to #87 -- we can use yaml2obj to generate known good and bad Mach-Os based on e.g. https://github.com/llvm-mirror/llvm/tree/master/test/Object/Inputs?rgh-link-date=2018-03-29T15%3A11%3A54.000Z

[BrewTestBot]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.

[woodruffw]

Bad bot. Sent from mobile. Please excuse my brevity.

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On Dec 22, 2020, at 7:14 PM, BrewTestBot ***@***.***> wrote:  Closed #201. — You are receiving this because you were assigned. Reply to this email directly, view it on GitHub, or unsubscribe.

[apainintheneck]

I'm curious as to what types of binary files you think should be added to the test suite. Also, there are like a million binary files in that folder you linked to in the LLVM project. If you didn't get around to testing all of those (at least the invalid ones), I think that's where I'll start.