Proposal for some useful functionalities.

[phlegx]

Hi @MatteoGabriele! Congratulation for this nice Vue package. Here some useful functionalities that can be added to vue-gtag to get better control over the plugin.

1. Add method to check if gtag DOM elements (script and link) are already included (with or without bootstrap() method).
2. Alternative: with method bootstrap() check before if gtag DOM elements (script and link) are already included to avoid duplicate gtag DOM elements. If already included don't add DOM elements.
3. Add method to remove (unload, inverse of bootstrap()) the gtag DOM elements.
4. Add possibility to exclude tracking on single route or all sub-routes in the tree by setting a meta value in routes definitions.
5. Split pageTrackerExcludedRoutes to two separate settings pageTrackerExcludedRoutePaths and pageTrackerExcludedRouteNames to speed up the code.

Here an example for proposal 4. and 5.:

const isRouteExcluded = (route) => {
  const { pageTrackerExcludedRoutePaths: paths, pageTrackerExcludedRouteNames: names } = getOptions();
  return paths.includes(route.path) || names.includes(route.name) || 
         route.meta.gtagExcludeRoute || route.matched.some((record) => record.meta.gtagExcludeRouteTree);
};

if (isRouteExcluded(to)) {
  return;
}