Update README.md

Author: davideast

README.md

@@ -5,7 +5,7 @@
 
 [![Build Status](https://travis-ci.org/angular/angularfire2.svg?branch=master)](https://travis-ci.org/angular/angularfire2) [![Join the chat at https://gitter.im/angular/angularfire2](https://badges.gitter.im/angular/angularfire2.svg)](https://gitter.im/angular/angularfire2?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
 
-Status: Alpha
+Status: Beta
 
 ## What is AngularFire2?
 
@@ -54,4 +54,4 @@ dangerous with AngularFire2.
 4. [Querying lists](docs/4-querying-lists.md)
 5. [User Authentication - FirebaseAuthentication](docs/5-user-authentication.md)
 
-## [API Reference](docs/api-reference.md)
+## [API Reference](docs/api-reference.md)