fix number/scroll script

[Hube2]

https://github.com/Hube2/acf-filters-and-functions/blob/master/correct-number-field-mouse-scrollwheel-action.php

Should be modified to add actions to number fields added to a document after the it has run. This should be possible by altering the jQuery selector rather than looping through each of the number fields in the document, just need to work out how.