TODO list for Perl module Handel

    - make tt2_cart.t tests to mimic xsp_cart.t tests
    - enhance demo sites to use full feature set
    - slim Cart taglib code to remove repeated code blocks left for clarity
    - start work on Handel::Order part of framework
    - find translation volunteer other than Google translate
    - clean up cart test variable names
    - add additional cart restore w/filter tests for multiple saved carts
    - figure out a centralized config scheme, possibly using XS/Handel.pm
    - add max quantity check to cart constraint
    - devise method for overriding constraints
    - add format attribute to <cart:price/> and <cart:subtotal>