Fine Generator Ignores lack of fines

[Thomas Berezansky]

In the event of a 0 fine rate, 0 fine interval, or 0 max fines the fine generator will still put in the effort to generate fines. This may be problematic, or at least cause lots of useless churn on some data.

In the case of the 0 fine interval it is likely to throw faults due to unchecked division by 0.

Attached is a quick patch to have the fine generator bail early on a circ that meets any of those three criteria, particularly before the fine interval is used in a division context.

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Signed-off-by: Thomas Berezansky <email address hidden>

[Bill Erickson (berick)]

Patch committed to trunk, rel_2_1, and rel_2_0. tsbere++