fix for nearIntegersPredicate

[Leobouloc]

Fixes unexpected behavior with zero-padded integers.

Previously:

>>> dedupe.predicates.nearIntegersPredicate('abc 0091 cfd')
{'0091', '90', '92'}

With fix:

>>> dedupe.predicates.nearIntegersPredicate('abc 0091 cfd')
{'92', '90', '91'}

[coveralls]

Coverage remained the same at 73.555% when pulling 830772f on eig-2017:fix_nearIntegersPredicate into 1b38234 on dedupeio:master.

[fgregg]

Thank you!