cmd/ursrv: Filter out ancient versions from chart

cmd/ursrv/static/index.html

@@ -21,7 +21,7 @@ found in the LICENSE file.
   <script src="https://cdnjs.cloudflare.com/ajax/libs/leaflet/0.7.7/leaflet.js"></script>
   <script src="https://cdn.jsdelivr.net/npm/heatmapjs@2.0.2/heatmap.min.js"></script>
   <script src="https://cdn.jsdelivr.net/npm/leaflet-heatmap@1.0.0/leaflet-heatmap.js"></script>
-    
+
   <style type="text/css">
     body {
       margin: 40px;
@@ -55,7 +55,10 @@ found in the LICENSE file.
     google.setOnLoadCallback(drawPerformanceCharts);
 
     function drawVersionChart() {
-      var jsonData = $.ajax({url: "summary.json", dataType:"json", async: false}).responseText;
+      // Summary version chart for versions that at some point in the chart
+      // reaches 250 devices. This filters out versions that are old and
+      // uninteresting yet linger forever with like four users.
+      var jsonData = $.ajax({url: "summary.json?min=250", dataType:"json", async: false}).responseText;
       var rows = JSON.parse(jsonData);
 
       var data = new google.visualization.DataTable();
@@ -224,7 +227,7 @@ found in the LICENSE file.
       var testData = {
         data: locations
       };
-      
+
       var baseLayer = L.tileLayer(
         'https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png',{
           attribution: '...',