going to implement frontend for report generating
successfully draw graph, going to implement date picker
going to add yearly sold product amount report
fix test failure by add default to some col in table
finish product sold report, going to implement income report
finish income report, going to implement profit plot
finish report feature
Merge branch 'feature/report' into develop
Merge branch 'develop' of github.com:CE-KMITL-OOAD-2014/online_shopping_system into develop