add test tooltip template

genome-vuer/src/js/app.js

@@ -5,7 +5,7 @@ var app = new Vue({
       id: "my-genome",
       start: 1706479,
       end: 1718084,
-      tooltip: null
+      tooltip: "name: {name}</br>description: {description}</br>start: {start}</br>end: {end}"
     },
     feature_data: [
       { name: "Gene 1",