Add response time badge and chart

vendor/github.com/wcharczuk/go-chart/v2/series.go

@@ -0,0 +1,10 @@
+package chart
+
+// Series is an alias to Renderable.
+type Series interface {
+	GetName() string
+	GetYAxis() YAxisType
+	GetStyle() Style
+	Validate() error
+	Render(r Renderer, canvasBox Box, xrange, yrange Range, s Style)
+}