Schema mod

I've cleaned up most of the really ugly testing code in base.js.  Also, I've added the ability to mark fields as hidden, which will prevent them from ever being returned to the user.  For example, this would be useful if you are using Autocrud to build a user object.  You would want the user to be able to manipulate their user settings, but it should never be possible for a user to read their password out of the database, only update it.