[docs] remove 'app' docs from v2 docs

docs/v2/core/app.md

@@ -1,34 +0,0 @@
-# App - firebase.app(): FirebaseApp
-
-RNFirebase supports both initializing apps natively and also via js code over the RN bridge.
-
-Apps initialized natively are available immediately at app runtime, there is no need to call `initializeApp` for them.
-
-For example, to access the default app initialized via the `Google-Services` `plist` or `json` file:
-```javascipt
-import firebase from 'react-native-firebase';
-
-const defaultApp = firebase.app();
-
-defaultApp.database().ref('foobar').once('value', (snapshot) => {
-  // snapshot from default app
-});
-
-// get the default app name/options that were initialized natively
-console.log("name", defaultApp.name);
-console.log("apiKey", defaultApp.options.apiKey);
-console.log("applicationId", defaultApp.options.applicationId);
-console.log("databaseUrl", defaultApp.options.databaseUrl);
-console.log("messagingSenderId", defaultApp.options.messagingSenderId);
-console.log("projectId", defaultApp.options.projectId);
-console.log("storageBucket", defaultApp.options.projectId);
-```
-
-
-TODO api ref docs:
-
- - name: String
- - options: Object
- - delete(): Promise
-
-

docs/v2/core/firebase.md

@@ -1,10 +0,0 @@
-# Firebase
-
-TODO api ref docs:
-
- - apps(): Array<FirebaseApp>
- - app(): FirebaseApp
- - initializeApp(): FirebaseApp
- - setLogLevel()
- - SDK_VERSION: String
- - googleApiAvailability: Object