laravel cart add code example

Example: Cart::total return number format value laravel

For the alternative https://github.com/bumbummen99/LaravelShoppingcart 
which is the forked project of https://github.com/Crinsane/LaravelShoppingcart 
and also support the latest Laravel versions.

There is a method called `Cart::totalFloat()` which will return you float value 
for the cart total.