Update rules.html
Update rules.html

Fixed spelling error in placeholder of date_between.
logaretm/vee-validate,baianat/vee-validate,logaretm/vee-validate,dfcook/vee-validate,dfcook/vee-validate,danielgranat/vee-validate,logaretm/vee-validate,baianat/vee-validate,baianat/vee-validate,danielgranat/vee-validate