Add a page to the web interface with a screenshot button

lib/obp60task/index.js

@@ -0,0 +1,12 @@
+(function(){
+    const api=window.esp32nmea2k;
+    if (! api) return;
+    const tabName="OBP60";
+    api.registerListener((id, data) => {
+    //    if (!data.testboard) return; //do nothing if we are not active
+        let page = api.addTabPage(tabName, "Screenshot");
+        api.addEl('button', '', page, 'Screenshot').addEventListener('click', function (ev) {
+	window.open('/api/user/OBP60Task/screenshot', 'screenshot');
+        })
+    }, api.EVENTS.init);
+})();