fix(singlestat gauge): better font size handling for gauge, now value font size…

fix(singlestat gauge): better font size handling for gauge, now value font size is used as scaling factor, fixes #4876

public/app/app.ts

@@ -42,6 +42,8 @@ export class GrafanaApp {
     app.constant('grafanaVersion', "@grafanaVersion@");
 
     app.config(($locationProvider, $controllerProvider, $compileProvider, $filterProvider, $provide) => {
+      //$compileProvider.debugInfoEnabled(false);
+
       this.registerFunctions.controller = $controllerProvider.register;
       this.registerFunctions.directive  = $compileProvider.directive;
       this.registerFunctions.factory    = $provide.factory;

public/app/plugins/panel/singlestat/module.ts

@@ -324,9 +324,9 @@ class SingleStatCtrl extends MetricsPanelCtrl {
         ? 'rgb(230,230,230)'
         : 'rgb(38,38,38)';
 
-
+      var fontScale = parseInt(panel.valueFontSize) / 100;
       var dimension = Math.min(width, height);
-      var fontSize = Math.min(dimension/4, 100);
+      var fontSize = Math.min(dimension/5, 100) * fontScale;
       var gaugeWidth = Math.min(dimension/6, 60);
       var thresholdMarkersWidth = gaugeWidth/5;
 
@@ -374,15 +374,6 @@ class SingleStatCtrl extends MetricsPanelCtrl {
       $.plot(plotCanvas, [plotSeries], options);
     }
 
-    function getGaugeFontSize() {
-      if (panel.valueFontSize) {
-        var num = parseInt(panel.valueFontSize.substring(0, panel.valueFontSize.length - 1));
-        return (30 * (num / 100)) + 15;
-      } else {
-        return 30;
-      }
-    }
-
     function addSparkline() {
       var width = elem.width() + 20;
       if (width < 30) {