goto-analyzer --simplify must write files in binary mode

[tautschnig]

Running goto-analyzer --simplify on Windows produced invalid goto binaries,
because writing 0xa was turned into 0xd0xa (CRLF). Any goto binary with >= 10
ireps would fail in this way. The CI'ed regression tests do not catch this as we
do not further process the resulting goto binaries.

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[allredj]

This PR failed Diffblue compatibility checks (cbmc commit: 1099d48).
Build URL: https://travis-ci.com/diffblue/test-gen/builds/87185577
Status will be re-evaluated on next push.
Please contact @peterschrammel, @thk123, or @allredj for support.

Common spurious failures:

• the cbmc commit has disappeared in the mean time (e.g. in a force-push)
• the author is not in the list of contributors (e.g. first-time contributors).

[kroening]

Should the simplification be part of goto-instrument?

[martin-cs]

Seems fine to me.

[martin-cs]

@kroening I don't think so. The concept behind goto-analyzer is "run an abstract interpreter then..." At the moment the "then" options include simplification but there are patches around for invariant generation, function summarisation, etc. which will modify the program. If we make goto-analyzer "read only" then all of the modification tasks will have to move to goto-instrument and we will have to replicate all of the abstract interpreter options and set-up there. I would rather keep goto-analyzer "run AI then ..." and goto-instrument for more syntactic / drastic changes. Even if this means migrating some of the AI functionality from goto-instrument.

Does that seem fair? I'll merge if you consider this resolved.