[story 007] [zxf&wxy] load shopping cart by erb and database
[story 007] [zxf&wxy] modify tthe shopping cart link and item link in index.html and cart.html
[story 007] [zxf&wxy] load shopping by erb
Merge branch 'master' of https://github.com/tw-preschool/letusgo-team-c
[story 007] [zxf&wxy] modify the shopping cart link and item link