Add color to prefix and postfix in singlestat

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

@@ -426,14 +426,16 @@ class SingleStatCtrl extends MetricsPanelCtrl {
       var body = '<div class="singlestat-panel-value-container">';
 
       if (panel.prefix) {
-        body += getSpan('singlestat-panel-prefix', panel.prefixFontSize, panel.prefix);
+        var prefix = applyColoringThresholds(data.value, panel.prefix);
+        body += getSpan('singlestat-panel-prefix', panel.prefixFontSize, prefix);
       }
 
       var value = applyColoringThresholds(data.value, data.valueFormatted);
       body += getSpan('singlestat-panel-value', panel.valueFontSize, value);
 
       if (panel.postfix) {
-        body += getSpan('singlestat-panel-postfix', panel.postfixFontSize, panel.postfix);
+        var postfix = applyColoringThresholds(data.value, panel.postfix);
+        body += getSpan('singlestat-panel-postfix', panel.postfixFontSize, postfix);
       }
 
       body += '</div>';