avoid negating LONG_MIN in cash_out()

[Zhihong Yu]

Hi,
In cash_out(), we have the following code:

    if (value < 0)
    {
        /* make the amount positive for digit-reconstruction loop */
        value = -value;

The negation cannot be represented in type long when the value is LONG_MIN.
It seems we can error out when LONG_MIN is detected instead of continuing
with computation.

Please take a look at the patch and provide your feedback.

Thanks

cash-out-of-range.patch
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