Most compilers should optimize it, but it doesn't hurt to inline and has a better name
now.

Remove unused file containing the old polynomial representation.

Refactor polynomial to be unsigned long array
Remove unused code
Fix md5 calculation on BE

Use the original loop order instead of an inverted order

closes #15394

Assert that an invalid value (2**n-1 for n = 8, 16, 32, 64) has not
been passed to the Lemire function.

When the input to Generator.integers was 2**32, the value 2**32-1
was being passed as the `rng` argument to the 32-bit Lemire method,
but that method requires `rng` be strictly less then 2**32-1.

The fix was to handle 2**32-1 by calling next_uint32 directly.
This also works for the legacy code without changing the stream
of random integers from `randint`.

Closes gh-16066.