This should also be a (small) performance improvement.

rewrite BoolBinopNode for the non-boolean result case to avoid potentially harmful coercions along the way

move type coercion in BoolBinopNode chains from analyse_types() completely to coerce_to() as we may not know the final type that might support all operand types (usually boolean, but potentially user provided types)

--HG--
extra : transplant_source : %94%F6%D1%0B%19%00%C5%87%83%0Dl%A4U%8Db%19r%E7%5C%DD

--HG--
extra : transplant_source : %97s8%E8ep%83%1E%3BGo%1C%C8%11%A67%81Y%0B%DD

This allows one to avoid duplicating code, motivated in particular
by the many closure tests.

complete struct stat in POSIX API