New RequestCookie Identifier and Caching storage

* New Identifier: requestcookie (choose for storage: cache, the session
will be expired), the cart could be reloaded from a http request,
example: the customer could save his cart link (email, hyperlink) and
reopen this later.
If there is no request, the cookie will be loaded.
* New Storage: Laravel Caching
* Config file
* Future, perhaps a database eloquent setup, Cart + Tax tables?
Merge pull request #11 from theodh/master

feature: RequestCookie Identifier and Caching storage