math::checked provides safe integer arithmetic functions that check for
overflow.

The functions add*, sub* and mul* perform wrapping integer arithmetic, with the
same semantics as the +, -, and * operators.

	const (res, overflow) = math::addi32(types::I32_MAX, 1);
	assert(res == types::I32_MIN);
	assert(overflow);

The functions sat_* perform saturating integer arithmetic, which clamp the
result value to the range of the type.

	const res = math::sat_addi32(types::I32_MAX, 1);
	assert(res == types::I32_MAX);
