Remove Min/Max fields on search page

Hi Dan,

Because you’re using a number field, the search page assumes you have a min/max range (ISBN is a not-as-common-case here. Mostly, folks use the number field for things like price, quantity, available, etc). You’d have to hack the plugin to remove that on a per-field basis at this time. But I agree that it could be useful, so we’ll add it to the development list for the future.