Added tests for remove item
Add author and copyright to Nitesi::Cart's POD.
Add id method to Nitesi::Cart class.
Fix Perl warning on removal of first item in the cart.
Adjustments to the testing
1) Remove Data::Dumper
2) Increment the amount of tests
3) Ensure to add the item to the cart before specifiying a hook
for removing the item.
Added 2 new tests
1) Test amount of items in cart after removing an item that
got caught by a hook. I also expanded the error message
from the hook to be a bit more specific.
2) Test the amount of items in the cart after removing an item
without a hook.