v0.9.1

• Added $firebaseAuth.$changeEmail() to change the email address associated with an existing account.
• $firebaseAuth.$createUser() is now fulfilled with a user object which contains the created user's uid.
• Added several minor performance improvements implemented by @jamestalmage.
• $firebaseAuth.$onAuth() now properly fires a digest loop upon changes in authentication state.
• Fixed an issue with $firebaseAuth.$offAuth() which prevented the callback from actually being unbound (thanks to @jamestalmage).
• Fixed a bug in $firebase.$remove() when deleting a Firebase query reference (thanks to @jamestalmage).
• Passing in credentials to the user management methods of $firebaseAuth as individual arguments has been deprecated in favor of a single credentials argument.
• Deprecated $firebaseAuth.$sendPasswordResetEmail() in favor of the functionally equivalent $firebaseAuth.$resetPassword().