Initial commit of Model Creator script

The 'entrada' script found in the root of the repository can now be used to create a new Model file based on a database table provided. The requisite information needed to build the file is asked of the user, but additional interactivity and the ability to step forwards and backwards in the file would be very useful, as well as some way to save/prepopulate some of the fields. Overall, it is functional, but could (and will) be better after another couple iterations.