Matomo web component

Move Matomo related initialization to its own web component. Use this web component in App-shell.

App-shell has two new parameters: matomo-url and matomo-site-id. These are required for tracking, but tracking is still optional.

packages/matomo/src/matomo.js

@@ -11,6 +11,7 @@ export class MatomoElement extends DBPLitElement {
         this.endpoint = '';
         this.siteId = -1;
         this.isRunning = false;
+        this.lastEvent = [];
     }
 
 
@@ -91,6 +92,11 @@ export class MatomoElement extends DBPLitElement {
             });
 
             this.isRunning = true;
+            if (this.lastEvent.length > 0) {
+                console.log('MatomoElement* (' + this.isRunning + '): ' + this.lastEvent[1] + ', ' + this.lastEvent[2]);
+                _paq.push(this.lastEvent);
+                this.lastEvent = [];
+            }
             return;
         }
         if (! loggedIn && this.isRunning) {
@@ -102,8 +108,11 @@ export class MatomoElement extends DBPLitElement {
 
     track (action, message) {
         console.log('MatomoElement (' + this.isRunning + '): ' + action + ', ' + message);
+        const event = ['trackEvent', action, message];
         if (this.isRunning) {
-            _paq.push(['trackEvent', action, message]);
+            _paq.push(event);
+        } else {
+            this.lastEvent = event;
         }
     }
 }