Update 1-install-and-setup.md (#474)

As for the latest angularcli@webpack release, the app.module.ts should be the file you must edit to import the Firebase provider. You're also exporting MyAppModule class and not bootstraping any module so it must be app.module.ts.

Author: caroso1222

docs/1-install-and-setup.md

@@ -35,7 +35,7 @@ Now that you have a new project setup, install AngularFire 2 and Firebase from n
 
 ### 3. Setup @NgModule
 
-Open `/src/main.ts`, inject the Firebase providers, and specify your Firebase configuration. 
+Open `/src/app/app.module.ts`, inject the Firebase providers, and specify your Firebase configuration. 
 This can be found in your project at [the Firebase Console](https://console.firebase.google.com):
 
 ```ts