Subscription stats: Make sure there can be no division by zero errors

sitescripts/logs/template/subscription.html

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       <tr>
         <td class="title" width="250">Reported period:</td>
         <td>Month {{month|monthname}} (<a href="{{overviewURL}}">To overview page</a>)</td>
       </tr>
     </table>
 
     <div class="block_title">Days of month</div>
     <div class="block">
       <table align="center" style="margin-bottom: 20px;">
         <tr align="bottom">
-          {%- set maxHits, maxBandwidth = day|max(attribute='hits'), day|max(attribute='bandwidth') %}
-          {%- set totalHits = day|sum(attribute='hits') %}
-          {%- set totalBandwidth = day|sum(attribute='bandwidth') %}
+          {%- set maxHits = day|max(attribute='hits')|ensuremin(1) %}
+          {%- set maxBandwidth = day|max(attribute='bandwidth')|ensuremin(1) %}
+          {%- set totalHits = day|sum(attribute='hits')|ensuremin(1) %}
+          {%- set totalBandwidth = day|sum(attribute='bandwidth')|ensuremin(1) %}
           {%- set dayCount = day|length %}
           {%- if currentMonth and dayCount > 1 %}
             {%- set totalHits = totalHits - day[-1].hits %}
             {%- set totalBandwidth = totalBandwidth - day[-1].bandwidth %}
             {%- set dayCount = dayCount - 1 %}
           {%- endif %}
           {%- for info in day %}
           <td align="center" style="vertical-align: bottom;">
             <div class="hitsChart vertical" title="Hits: {{info.hits}}" style="height: {{(info.hits / maxHits * 100)|round(method='ceil')|int}}px;"></div>
             {{- '' -}}
@@ skipping 305 matching lines @@
           <td class="chart">
             <div class="hitsChart horizontal" style="width: {{(info.hits / maxHits * 100)|round(method='ceil')|int}}px;"></div><br />
             <div class="bandwidthChart horizontal" style="width: {{(info.bandwidth / maxBandwidth * 100)|round(method='ceil')|int}}px;"></div>
           </td>
         </tr>
         {%- endfor %}
       </table>
     </div>
   </body>
 </html>