Do not specify all files in libraries_info hook

As mentioned in the Stripe API Readme, it is not needed to specify all of the includes in the Stripe API Library, since the init.php file loads them all.

This will allow us to not require X-Autoload module, for instance, nor are we forced to use Composer to build the Library. Technically this method makes the code footprint somewhat bigger, due to the fact that we aren't specifying the includes we need, but I feel this is overall the best long-term approach.

Note that this does NOT require X-Autoload in order to work. The init.php file loads all /lib files via a require_once() call on each, and so the library works as expected.