DIV-749: ensure positive value for arrears amount

edivorce/apps/core/templates/question/06_children_payor_medical.html

@@ -285,7 +285,7 @@
     <div class="question-well" id="arrears_amount_question" hidden>
         <h3>What is the amount as of today's date?</h3>
         <div class="dollar-prefix">
-            {% money_input_field name="child_support_arrears_amount" class="money form-control input-narrow" min="0" %}
+            {% money_input_field name="child_support_arrears_amount" class="money positive-integer form-control input-narrow" min="0" %}
         </div>
     </div>
 {% endblock %}