CRITICAL UPDATE

This revision includes the following changes:
 - [1] book/index.php was updated to include the initialization script for the jQuery Book Purchasing plugin, allowing the user purchase books on this page.
 - [2] the FFI_BE_Buy.js jQuery plugin was updated to listen to clicks from both buttons and <span> tags with the "purchase" class to initiate a purchase request.
 - [3] buy.min.js reflects the changes made to the FFI_BE_Buy.js jQuery plugin.
 - [4] the Book class had the query inside of the details() method updated to fetch all available details on a book from the new database model.
 - [5] the Email_Base class was updated to fetch the API key for Mandrill from the database correctly from the new database model.
 - [6] the Purchase_Process class had several areas where data was fetched, gathered, and used, updated to fit the new names in the updated database model