SQLAuthLogic and SQLRestAuth call user_model class method

[davexunit]

First I want to apologize for not noticing this before. I did a search for other SQL authenticators that expect to use the class method user_model and found these two.

[davexunit]

I think that the correct patch for both of these cases is to call the user_models class method and fetch the value for the key @options[:auth_index]. That will retrieve the correct user model class.