Consistent division by zero semantics

[oscbyspro]

When dividing by zero, Swift has the semantics of returning the truncated (if needed) dividend. Currently, I'm returning the divisor for single digit remainder operations because the dividend may not fit in the remainder type. At some point, I changed this in Numberick when I concluded that being consistent is better. These values are junk by definition, but consistent junk is better than inconsistent junk.

TL;DR: division by zero will return the truncated dividend similar to Swift's stdlib.