welcome dialog; order UI facelift

src/track.js

@@ -0,0 +1,12 @@
+export let tracking_enabled = true
+
+export function track(event, info) {
+    if (tracking_enabled) {
+        if (window.gtag !== undefined)
+            window.gtag('event', event, info)
+        else {
+            console.log('gtag not available')
+            tracking_enabled = false
+        }
+    }
+}