Add Fullscreen in viewer, Track links with Google Analytics, Use .env file

- Fullscreen is a component that watches a store value set by the Carousel component on a picture click
- Use a .env file for API and website related settings and informations
- Google Analytics is now in place, tracking each routes link and viewer photo change

src/utils/functions.js

@@ -175,3 +175,15 @@ export const parallaxAnime = (element, anime) => {
         }
     }
 }
+
+
+/*
+** Google Analytics send page
+*/
+export const analyticsUpdate = (page, id = process.env.CONFIG.GA_TRACKER_ID) => {
+    if (typeof gtag !== 'undefined') {
+        window.gtag('config', id, {
+            page_path: page
+        })
+    }
+}