refactor the schema

lib/two_factor_authentication/schema.rb

@@ -1,7 +1,10 @@
 module TwoFactorAuthentication
   module Schema
-    def two_factor_authenticatable
+    def second_factor_pass_code
       apply_devise_schema :second_factor_pass_code, String, :limit => 32
+    end
+
+    def second_factor_attempts_count
       apply_devise_schema :second_factor_attempts_count, Integer, :default => 0
     end
   end