Merge manifest.json and site.webmanifest

Problem When you use OneSignal, it will generate a manifest.json for gcm_sender_id. When you use RealFaviconGenerator, it will generate a site.webmanifest for Android favicon. But there should be only one rel=”manifest” tag in your page. Reference: https://documentation.onesignal.com/docs/web-push-setup-faq#section-what-if-there-is-already-a-manifest-on-my-site- The manifest.json site.webmanifest Solution Merge them together and only put one manifest tag in your page header