@IBAction func createAccount(sender: AnyObject) {

    var username = usernameField.text
    var email = emailField.text
    var password = passwordField.text
    if username != "" && email != "" && password != "" {
        FIRAuth.auth()?.createUserWithEmail(email!, password: password!, completion: { (user, error) in
            databaseRef.child("users/(user.uid)/username").setValue(username)
            databaseRef.child("users/(user.uid)/password").setValue(password)
            databaseRef.child("users/(user.uid)/uid").setValue(user?.uid)
        })
    } else {
        print("please complete all fields")
    }
}